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448271 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/448271/what-is-init-py-for | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 448,271 | What is __init__.py for? | 3,942 | 2,801,807 | 14 | true | true | [
"python",
"module",
"package",
"python-packaging"
] | 2009-01-15T20:09:09 | 2024-10-26T06:18:34 | Mat | false | CC BY-SA 4.0 | 448,279 | 42,974 | 87,620 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What is __init__.py for in a Python source directory? | <p>What is <a href="https://docs.python.org/3/tutorial/modules.html#packages" rel="noreferrer"><code>__init__.py</code></a> for in a Python source directory?</p>
| [
{
"answerId": 448279,
"score": 2116,
"isAccepted": true,
"createdAt": "2009-01-15T20:13:24",
"ownerDisplayName": "Loki",
"ownerUserId": 39057,
"bodyText": "It used to be a required part of a package ( old, pre-3.3 \"regular package\" , not newer 3.3+ \"namespace package\" ). Here's the d... | 1 |
606191 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/606191/convert-bytes-to-a-string-in-python-3 | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 606,191 | Convert bytes to a string in Python 3 | 3,887 | 5,412,477 | 23 | true | true | [
"python",
"string",
"python-3.x"
] | 2009-03-03T12:23:01 | 2025-01-06T01:58:20 | Tomas Sedovic | false | CC BY-SA 4.0 | 606,199 | 2,239 | 44,783 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I captured the standard output of an external program into a bytes object: >>> from subprocess import * >>> stdout = Popen(['ls', '-l'], stdout=PIPE).communicate()[0] >>> stdout b'total 0\n-rw-rw-r-- 1 thomas thomas 0 Mar 3 07:03 file1\n-rw-rw-r-- 1 thomas thomas 0 Mar 3 07:03 file2\n' I want to convert that to a norma... | <p>I captured the standard output of an external program into a <code>bytes</code> object:</p>
<pre><code>>>> from subprocess import *
>>> stdout = Popen(['ls', '-l'], stdout=PIPE).communicate()[0]
>>> stdout
b'total 0\n-rw-rw-r-- 1 thomas thomas 0 Mar 3 07:03 file1\n-rw-rw-r-- 1 thomas thom... | [
{
"answerId": 606199,
"score": 5881,
"isAccepted": true,
"createdAt": "2009-03-03T12:26:18",
"ownerDisplayName": "Aaron Maenpaa",
"ownerUserId": 2603,
"bodyText": "Decode the bytes object to produce a string: >>> b\"abcde\".decode(\"utf-8\") 'abcde' The above example assumes that the byt... | 1 |
1436703 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1436703/what-is-the-difference-between-str-and-repr | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,436,703 | What is the difference between __str__ and __repr__? | 3,841 | 1,101,188 | 29 | true | true | [
"python",
"magic-methods",
"repr"
] | 2009-09-17T04:27:45 | 2025-08-07T18:37:34 | Casebash | false | CC BY-SA 4.0 | 2,626,364 | 165,495 | 120,251 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What is the difference between __str__ and __repr__ in Python? | <p>What is the difference between <a href="https://docs.python.org/3/reference/datamodel.html#object.__str__" rel="noreferrer"><code>__str__</code></a> and <a href="https://docs.python.org/3/reference/datamodel.html#object.__repr__" rel="noreferrer"><code>__repr__</code></a> in Python?</p>
| [
{
"answerId": 2626364,
"score": 3633,
"isAccepted": true,
"createdAt": "2010-04-13T00:56:52",
"ownerDisplayName": "moshez",
"ownerUserId": 122683,
"bodyText": "Alex Martelli summarized well but, surprisingly, was too succinct. First, let me reiterate the main points in Alex ’s post: The ... | 1 |
17071871 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/17071871/how-do-i-select-rows-from-a-dataframe-based-on-column-values | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 17,071,871 | How do I select rows from a DataFrame based on column values? | 3,635 | 6,893,382 | 20 | true | true | [
"python",
"pandas",
"dataframe",
"indexing",
"filter"
] | 2013-06-12T17:42:05 | 2025-05-14T01:53:58 | szli | false | CC BY-SA 4.0 | 17,071,908 | 458,429 | 39,429 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How can I select rows from a DataFrame based on values in some column in Pandas? In SQL, I would use: SELECT * FROM table WHERE column_name = some_value | <p>How can I select rows from a DataFrame based on values in some column in Pandas?</p>
<p>In SQL, I would use:</p>
<pre class="lang-sql prettyprint-override"><code>SELECT *
FROM table
WHERE column_name = some_value
</code></pre>
| [
{
"answerId": 17071908,
"score": 6653,
"isAccepted": true,
"createdAt": "2013-06-12T17:44:20",
"ownerDisplayName": "unutbu",
"ownerUserId": 190597,
"bodyText": "To select rows whose column value equals a scalar, some_value , use == : df.loc[df['column_name'] == some_value] To select rows... | 1 |
1024847 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1024847/how-can-i-add-new-keys-to-a-dictionary | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,024,847 | How can I add new keys to a dictionary? | 3,601 | 5,645,894 | 20 | true | true | [
"python",
"dictionary",
"key",
"lookup"
] | 2009-06-21T22:07:39 | 2025-03-18T16:37:01 | lfaraone | false | CC BY-SA 4.0 | 1,024,851 | 90,777 | 50,872 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I add a new key to an existing dictionary? It doesn't have an .add() method. | <p>How do I add a new key to an existing dictionary? It doesn't have an <code>.add()</code> method.</p>
| [
{
"answerId": 1024851,
"score": 4464,
"isAccepted": true,
"createdAt": "2009-06-21T22:09:06",
"ownerDisplayName": "Paolo Bergantino",
"ownerUserId": 16417,
"bodyText": "You create a new key/value pair on a dictionary by assigning a value to that key d = {'key': 'value'} print(d) # {'key'... | 1 |
3437059 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/3437059/does-python-have-a-string-contains-substring-method | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 3,437,059 | Does Python have a string 'contains' substring method? | 3,585 | 7,545,827 | 10 | true | true | [
"python",
"string",
"substring",
"contains"
] | 2010-08-09T02:52:50 | 2025-01-17T16:59:58 | Blankman | false | CC BY-SA 3.0 | 3,437,070 | 39,677 | 268,914 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I'm looking for a string.contains or string.indexof method in Python. I want to do: if not somestring.contains("blah"): continue | <p>I'm looking for a <code>string.contains</code> or <code>string.indexof</code> method in Python.</p>
<p>I want to do:</p>
<pre><code>if not somestring.contains("blah"):
continue
</code></pre>
| [
{
"answerId": 3437070,
"score": 8685,
"isAccepted": true,
"createdAt": "2010-08-09T02:56:21",
"ownerDisplayName": "Michael Mrozek",
"ownerUserId": 309308,
"bodyText": "Use the in operator : if \"blah\" not in somestring: continue Note: This is case-sensitive."
}
] | 1 |
6996603 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/6996603/how-can-i-delete-a-file-or-folder-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 6,996,603 | How can I delete a file or folder in Python? | 3,554 | 4,058,628 | 18 | true | true | [
"python",
"file-io",
"directory",
"delete-file"
] | 2011-08-09T13:05:42 | 2024-04-29T09:36:08 | Zygimantas | false | CC BY-SA 4.0 | 6,996,628 | 854,002 | 35,881 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How can I delete a file or folder in Python? | <p>How can I delete a file or folder in Python?</p>
| [
{
"answerId": 6996628,
"score": 5060,
"isAccepted": true,
"createdAt": "2011-08-09T13:07:39",
"ownerDisplayName": "RichieHindle",
"ownerUserId": 21886,
"bodyText": "Use one of these methods: pathlib.Path.unlink() removes a file or symbolic link. pathlib.Path.rmdir() removes an empty dire... | 1 |
1132941 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1132941/least-astonishment-and-the-mutable-default-argument | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,132,941 | "Least Astonishment" and the Mutable Default Argument | 3,511 | 301,155 | 34 | true | true | [
"python",
"language-design",
"default-parameters",
"least-astonishment"
] | 2009-07-15T18:00:37 | 2025-08-12T22:31:16 | Stefano Borini | false | CC BY-SA 4.0 | 1,145,781 | 78,374 | 145,268 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | def foo(a=[]): a.append(5) return a Python novices expect this function called with no parameter to always return a list with only one element: [5] . The result is different and astonishing: >>> foo() [5] >>> foo() [5, 5] >>> foo() [5, 5, 5] >>> foo() [5, 5, 5, 5] >>> foo() The behavior has an underlying explanation, b... | <pre><code>def foo(a=[]):
a.append(5)
return a
</code></pre>
<p>Python novices expect this function called with no parameter to always return a list with only one element: <code>[5]</code>. The result is different and astonishing:</p>
<pre><code>>>> foo()
[5]
>>> foo()
[5, 5]
>>> foo... | [
{
"answerId": 1145781,
"score": 1963,
"isAccepted": true,
"createdAt": "2009-07-17T21:29:39",
"ownerDisplayName": "rob",
"ownerUserId": 43927,
"bodyText": "Actually, this is not a design flaw, and it is not because of internals or performance. It comes simply from the fact that functions... | 1 |
36901 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/36901/what-does-double-star-asterisk-and-star-asterisk-do-for-parameters | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 36,901 | What does ** (double star/asterisk) and * (star/asterisk) do for parameters? | 3,501 | 1,556,482 | 28 | true | true | [
"python",
"syntax",
"parameter-passing",
"variadic-functions",
"argument-unpacking"
] | 2008-08-31T15:04:35 | 2026-06-03T04:41:03 | Todd | false | CC BY-SA 4.0 | 36,908 | 2,572 | 36,380 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What do *args and **kwargs mean in these function definitions? def foo(x, y, *args): pass def bar(x, y, **kwargs): pass See What do ** (double star/asterisk) and * (star/asterisk) mean in a function call? for the complementary question about arguments. | <p>What do <code>*args</code> and <code>**kwargs</code> mean in these function definitions?</p>
<pre><code>def foo(x, y, *args):
pass
def bar(x, y, **kwargs):
pass
</code></pre>
<hr />
<p><sub>See <a href="https://stackoverflow.com/questions/2921847">What do ** (double star/asterisk) and * (star/asterisk) mean... | [
{
"answerId": 36908,
"score": 3348,
"isAccepted": true,
"createdAt": "2008-08-31T15:17:31",
"ownerDisplayName": "Peter Hoffmann",
"ownerUserId": 720,
"bodyText": "The *args and **kwargs are common idioms to allow an arbitrary number of arguments to functions, as described in the section ... | 1 |
4906977 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4906977/how-can-i-access-environment-variables-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,906,977 | How can I access environment variables in Python? | 3,476 | 3,519,584 | 17 | true | true | [
"python",
"environment-variables"
] | 2011-02-05T13:03:35 | 2024-02-12T16:18:05 | Amit Yadav | false | CC BY-SA 4.0 | 4,907,053 | 601,738 | 35,866 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How can I get the value of an environment variable in Python? | <p>How can I get the value of an environment variable in Python?</p>
| [
{
"answerId": 4907053,
"score": 4869,
"isAccepted": true,
"createdAt": "2011-02-05T13:18:00",
"ownerDisplayName": "Rod",
"ownerUserId": 64633,
"bodyText": "Environment variables are accessed through os.environ : import os print(os.environ['HOME']) To see a list of all environment variabl... | 1 |
613183 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/613183/how-do-i-sort-a-dictionary-by-value | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 613,183 | How do I sort a dictionary by value? | 3,413 | 5,839,599 | 34 | true | true | [
"python",
"sorting",
"dictionary"
] | 2009-03-05T00:49:05 | 2025-07-16T09:04:20 | Gern Blanston | false | CC BY-SA 4.0 | 613,218 | 2,786 | 42,680 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have a dictionary of values read from two fields in a database: a string field and a numeric field. The string field is unique, so that is the key of the dictionary. I can sort on the keys, but how can I sort based on the values? Note: I have read Stack Overflow question here How do I sort a list of dictionaries by a... | <p>I have a dictionary of values read from two fields in a database: a string field and a numeric field. The string field is unique, so that is the key of the dictionary.</p>
<p>I can sort on the keys, but how can I sort based on the values?</p>
<p>Note: I have read Stack Overflow question here <em><a href="https://s... | [
{
"answerId": 613218,
"score": 7099,
"isAccepted": true,
"createdAt": "2009-03-05T00:59:34",
"ownerDisplayName": "Devin Jeanpierre",
"ownerUserId": 18515,
"bodyText": "Python 3.7+ or CPython 3.6 Dicts preserve insertion order in Python 3.7+. Same in CPython 3.6, but it's an implementatio... | 1 |
2612802 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2612802/how-do-i-clone-a-list-so-that-it-doesnt-change-unexpectedly-after-assignment | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,612,802 | How do I clone a list so that it doesn't change unexpectedly after assignment? | 3,371 | 2,303,961 | 25 | true | true | [
"python",
"list",
"clone",
"mutable"
] | 2010-04-10T08:49:46 | 2025-12-21T05:36:37 | aF. | false | CC BY-SA 4.0 | 2,612,815 | 187,730 | 67,093 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | While using new_list = my_list , any modifications to new_list changes my_list every time. Why is this, and how can I clone or copy the list to prevent it? For example: >>> my_list = [1, 2, 3] >>> new_list = my_list >>> new_list.append(4) >>> my_list [1, 2, 3, 4] | <p>While using <code>new_list = my_list</code>, any modifications to <code>new_list</code> changes <code>my_list</code> every time. Why is this, and how can I clone or copy the list to prevent it? For example:</p>
<pre><code>>>> my_list = [1, 2, 3]
>>> new_list = my_list
>>> new_list.append(4... | [
{
"answerId": 2612815,
"score": 4158,
"isAccepted": true,
"createdAt": "2010-04-10T08:55:21",
"ownerDisplayName": "Felix Kling",
"ownerUserId": 218196,
"bodyText": "new_list = my_list doesn't actually create a second list. The assignment just copies the reference to the list, not the act... | 1 |
986006 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/986006/how-do-i-pass-a-variable-by-reference | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 986,006 | How do I pass a variable by reference? | 3,364 | 2,218,487 | 44 | true | true | [
"python",
"reference",
"parameter-passing",
"pass-by-reference"
] | 2009-06-12T10:23:51 | 2025-10-14T23:11:08 | David Sykes | false | CC BY-SA 4.0 | 986,145 | 259 | 50,122 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I wrote this class for testing: class PassByReference: def __init__(self): self.variable = 'Original' self.change(self.variable) print(self.variable) def change(self, var): var = 'Changed' When I tried creating an instance, the output was Original . So it seems like parameters in Python are passed by value. Is that cor... | <p>I wrote this class for testing:</p>
<pre><code>class PassByReference:
def __init__(self):
self.variable = 'Original'
self.change(self.variable)
print(self.variable)
def change(self, var):
var = 'Changed'
</code></pre>
<p>When I tried creating an instance, the output was <code... | [
{
"answerId": 986145,
"score": 3596,
"isAccepted": true,
"createdAt": "2009-06-12T11:18:27",
"ownerDisplayName": "Blair Conrad",
"ownerUserId": 1199,
"bodyText": "Arguments are passed by assignment . The rationale behind this is twofold: the parameter passed in is actually a reference to... | 1 |
2052390 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2052390/manually-raising-throwing-an-exception-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,052,390 | Manually raising (throwing) an exception in Python | 3,322 | 3,379,634 | 11 | true | true | [
"python",
"exception"
] | 2010-01-12T21:07:40 | 2025-07-12T13:46:05 | TIMEX | false | CC BY-SA 4.0 | 24,065,533 | 179,736 | 275,536 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I raise an exception in Python so that it can later be caught via an except block? | <p>How do I raise an exception in Python so that it can later be caught via an <code>except</code> block?</p>
| [
{
"answerId": 24065533,
"score": 4329,
"isAccepted": true,
"createdAt": "2014-06-05T16:30:58",
"ownerDisplayName": "Aaron Hall",
"ownerUserId": 541136,
"bodyText": "How do I manually throw/raise an exception in Python? Use the most specific Exception constructor that semantically fits yo... | 1 |
576169 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/576169/understanding-python-super-with-init-methods | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 576,169 | Understanding Python super() with __init__() methods | 3,298 | 2,981,060 | 7 | true | true | [
"python",
"class",
"oop",
"inheritance",
"super"
] | 2009-02-23T00:30:08 | 2024-04-02T17:51:25 | Mizipzor | true | null | 576,183 | 56,763 | 52,749 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Why is super() used? Is there a difference between using Base.__init__ and super().__init__ ? class Base(object): def __init__(self): print "Base created" class ChildA(Base): def __init__(self): Base.__init__(self) class ChildB(Base): def __init__(self): super(ChildB, self).__init__() ChildA() ChildB() | <p>Why is <code>super()</code> used?</p>
<p>Is there a difference between using <code>Base.__init__</code> and <code>super().__init__</code>?</p>
<pre><code>class Base(object):
def __init__(self):
print "Base created"
class ChildA(Base):
def __init__(self):
Base.__init__(self)... | [
{
"answerId": 576183,
"score": 2382,
"isAccepted": true,
"createdAt": "2009-02-23T00:37:31",
"ownerDisplayName": "Kiv",
"ownerUserId": 49559,
"bodyText": "super() lets you avoid referring to the base class explicitly, which can be nice. But the main advantage comes with multiple inherita... | 1 |
1720421 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1720421/how-do-i-concatenate-two-lists-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,720,421 | How do I concatenate two lists in Python? | 3,237 | 4,907,006 | 31 | true | true | [
"python",
"list",
"concatenation"
] | 2009-11-12T07:04:09 | 2024-01-10T20:15:51 | y2k | false | CC BY-SA 4.0 | 1,720,432 | 206,504 | 66,254 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I concatenate two lists in Python? Example: listone = [1, 2, 3] listtwo = [4, 5, 6] Expected outcome: >>> joinedlist [1, 2, 3, 4, 5, 6] | <p>How do I concatenate two lists in Python?</p>
<p>Example:</p>
<pre><code>listone = [1, 2, 3]
listtwo = [4, 5, 6]
</code></pre>
<p>Expected outcome:</p>
<pre><code>>>> joinedlist
[1, 2, 3, 4, 5, 6]
</code></pre>
| [
{
"answerId": 1720432,
"score": 5641,
"isAccepted": true,
"createdAt": "2009-11-12T07:07:06",
"ownerDisplayName": "Daniel G",
"ownerUserId": 207432,
"bodyText": "Use the + operator to combine the lists: listone = [1, 2, 3] listtwo = [4, 5, 6] joinedlist = listone + listtwo Output: >>> jo... | 1 |
53513 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/53513/how-do-i-check-if-a-list-is-empty | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 53,513 | How do I check if a list is empty? | 3,222 | 5,405,158 | 27 | true | true | [
"python",
"list"
] | 2008-09-10T06:20:11 | 2026-07-06T03:45:10 | Ray | false | CC BY-SA 4.0 | 53,522 | 4,872 | 194,066 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | For example, if passed the following: a = [] How do I check to see if a is empty? | <p>For example, if passed the following:</p>
<pre><code>a = []
</code></pre>
<p>How do I check to see if <code>a</code> is empty?</p>
| [
{
"answerId": 53522,
"score": 7318,
"isAccepted": true,
"createdAt": "2008-09-10T06:28:05",
"ownerDisplayName": "Patrick",
"ownerUserId": 429,
"bodyText": "if not a: print(\"List is empty\") Using the implicit booleanness of the empty list is quite Pythonic."
}
] | 1 |
739654 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/739654/how-do-i-make-function-decorators-and-chain-them-together | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 739,654 | How do I make function decorators and chain them together? | 3,202 | 699,294 | 22 | true | true | [
"python",
"function",
"decorator",
"python-decorators",
"chain"
] | 2009-04-11T07:05:31 | 2023-10-08T00:52:58 | Imran | false | CC BY-SA 4.0 | 739,665 | 1,897 | 91,875 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I make two decorators in Python that would do the following? @make_bold @make_italic def say(): return "Hello" Calling say() should return: "<b><i>Hello</i></b>" | <p>How do I make two decorators in Python that would do the following?</p>
<pre><code>@make_bold
@make_italic
def say():
return "Hello"
</code></pre>
<p>Calling <code>say()</code> should return:</p>
<pre><code>"<b><i>Hello</i></b>"
</code></pre>
| [
{
"answerId": 1594484,
"score": 4896,
"isAccepted": false,
"createdAt": "2009-10-20T13:05:46",
"ownerDisplayName": "Bite code",
"ownerUserId": 9951,
"bodyText": "If you are not into long explanations, see Paolo Bergantino’s answer . Decorator Basics Python’s functions are objects To unde... | 2 |
312443 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/312443/how-do-i-split-a-list-into-equally-sized-chunks | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 312,443 | How do I split a list into equally-sized chunks? | 3,181 | 1,796,140 | 69 | true | true | [
"python",
"list",
"split",
"chunks"
] | 2008-11-23T12:15:52 | 2026-02-08T23:06:55 | jespern | false | CC BY-SA 4.0 | 312,464 | 112,415 | 33,576 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I split a list of arbitrary length into equal sized chunks? See also: How to iterate over a list in chunks . To chunk strings, see Split string every nth character? . | <p>How do I split a list of arbitrary length into equal sized chunks?</p>
<hr />
<p><sub>See also: <a href="https://stackoverflow.com/q/434287">How to iterate over a list in chunks</a>.<br />
To chunk strings, see <a href="https://stackoverflow.com/questions/9475241">Split string every nth character?</a>.</sub></p>
| [
{
"answerId": 312464,
"score": 4506,
"isAccepted": true,
"createdAt": "2008-11-23T12:33:53",
"ownerDisplayName": "Ned Batchelder",
"ownerUserId": 14343,
"bodyText": "Here's a generator that yields evenly-sized chunks: def chunks(lst, n): \"\"\"Yield successive n-sized chunks from lst.\"\... | 1 |
5137497 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/5137497/find-the-current-directory-and-files-directory | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 5,137,497 | Find the current directory and file's directory | 3,144 | 5,513,037 | 13 | true | true | [
"python",
"directory"
] | 2011-02-28T01:51:21 | 2023-03-15T08:40:13 | John Howard | true | null | 5,137,509 | 374,797 | 65,043 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I determine: the current directory (where I was in the shell when I ran the Python script), and where the Python file I am executing is? | <p>How do I determine:</p>
<ol>
<li>the current directory (where I was in the shell when I ran the Python script), and</li>
<li>where the Python file I am executing is?</li>
</ol>
| [
{
"answerId": 5137509,
"score": 4848,
"isAccepted": true,
"createdAt": "2011-02-28T01:54:18",
"ownerDisplayName": "Russell Dias",
"ownerUserId": 322129,
"bodyText": "To get the full path to the directory a Python file is contained in, write this in that file: import os dir_path = os.path... | 1 |
252703 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/252703/what-is-the-difference-between-pythons-list-methods-append-and-extend | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 252,703 | What is the difference between Python's list methods append and extend? | 3,109 | 3,327,880 | 20 | true | true | [
"python",
"list",
"data-structures",
"append",
"extend"
] | 2008-10-31T05:55:36 | 2024-04-24T20:34:06 | Claudiu | false | CC BY-SA 4.0 | 252,711 | 15,055 | 231,141 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What's the difference between the list methods append() and extend() ? | <p>What's the difference between the list methods <code>append()</code> and <code>extend()</code>?</p>
| [
{
"answerId": 252711,
"score": 5933,
"isAccepted": true,
"createdAt": "2008-10-31T06:02:25",
"ownerDisplayName": "kender",
"ownerUserId": 4172,
"bodyText": ".append() appends a single object at the end of the list: >>> x = [1, 2, 3] >>> x.append([4, 5]) >>> print(x) [1, 2, 3, [4, 5]] .ex... | 1 |
11346283 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/11346283/renaming-column-names-in-pandas | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 11,346,283 | Renaming column names in Pandas | 3,074 | 7,035,834 | 33 | true | true | [
"python",
"pandas",
"replace",
"dataframe",
"rename"
] | 2012-07-05T14:21:15 | 2025-05-23T08:56:42 | user1504276 | false | CC BY-SA 4.0 | 11,346,337 | 1,504,276 | 30,835 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to change the column labels of a Pandas DataFrame from ['$a', '$b', '$c', '$d', '$e'] to ['a', 'b', 'c', 'd', 'e'] | <p>I want to change the column labels of a Pandas DataFrame from</p>
<pre><code>['$a', '$b', '$c', '$d', '$e']
</code></pre>
<p>to</p>
<pre><code>['a', 'b', 'c', 'd', 'e']
</code></pre>
| [
{
"answerId": 11354850,
"score": 4718,
"isAccepted": false,
"createdAt": "2012-07-06T01:48:15",
"ownerDisplayName": "lexual",
"ownerUserId": 1505540,
"bodyText": "Rename Specific Columns Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be rena... | 2 |
30081275 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/30081275/why-is-1000000000000000-in-range1000000000000001-so-fast-in-python-3 | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 30,081,275 | Why is "1000000000000000 in range(1000000000000001)" so fast in Python 3? | 3,069 | 385,681 | 12 | true | true | [
"python",
"performance",
"python-3.x",
"range",
"python-internals"
] | 2015-05-06T15:32:43 | 2023-05-19T08:43:44 | Rick | false | CC BY-SA 4.0 | 30,081,318 | 2,437,514 | 45,759 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | It is my understanding that the range() function, which is actually an object type in Python 3 , generates its contents on the fly, similar to a generator. This being the case, I would have expected the following line to take an inordinate amount of time because, in order to determine whether 1 quadrillion is in the ra... | <p>It is my understanding that the <code>range()</code> function, which is actually <a href="https://docs.python.org/3/library/stdtypes.html#typesseq-range" rel="noreferrer">an object type in Python 3</a>, generates its contents on the fly, similar to a generator.</p>
<p>This being the case, I would have expected the f... | [
{
"answerId": 30081318,
"score": 3130,
"isAccepted": true,
"createdAt": "2015-05-06T15:33:58",
"ownerDisplayName": "Martijn Pieters",
"ownerUserId": 100297,
"bodyText": "The Python 3 range() object doesn't produce numbers immediately; it is a smart sequence object that produces numbers o... | 1 |
11277432 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/11277432/how-can-i-remove-a-key-from-a-python-dictionary | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 11,277,432 | How can I remove a key from a Python dictionary? | 3,023 | 3,132,797 | 11 | true | true | [
"python",
"dictionary",
"unset"
] | 2012-06-30T20:27:59 | 2024-11-02T13:47:58 | Tony | false | CC BY-SA 4.0 | 11,277,439 | 692,499 | 38,801 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to remove a key from a dictionary if it is present. I currently use this code: if key in my_dict: del my_dict[key] Without the if statement, the code will raise KeyError if the key is not present. How can I handle this more simply? See Delete an element from a dictionary for more general approaches to the proble... | <p>I want to remove a key from a dictionary if it is present. I currently use this code:</p>
<pre class="lang-py prettyprint-override"><code>if key in my_dict:
del my_dict[key]
</code></pre>
<p>Without the <code>if</code> statement, the code will raise <code>KeyError</code> if the key is <em>not</em> present. How c... | [
{
"answerId": 11277439,
"score": 4828,
"isAccepted": true,
"createdAt": "2012-06-30T20:29:18",
"ownerDisplayName": "Sven Marnach",
"ownerUserId": 279627,
"bodyText": "To delete a key regardless of whether it is in the dictionary, use the two-argument form of dict.pop() : my_dict.pop('key... | 1 |
466345 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/466345/convert-string-jun-1-2005-133pm-into-datetime | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 466,345 | Convert string "Jun 1 2005 1:33PM" into datetime | 3,005 | 4,732,556 | 26 | true | true | [
"python",
"datetime",
"type-conversion"
] | 2009-01-21T18:00:29 | 2024-07-10T01:05:18 | Oli | false | CC BY-SA 4.0 | 466,376 | 12,870 | 240,946 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have a huge list of datetime strings like the following ["Jun 1 2005 1:33PM", "Aug 28 1999 12:00AM"] How do I convert them into datetime objects? | <p>I have a huge list of datetime strings like the following</p>
<pre class="lang-py prettyprint-override"><code>["Jun 1 2005 1:33PM", "Aug 28 1999 12:00AM"]
</code></pre>
<p>How do I convert them into <a href="https://docs.python.org/3/library/datetime.html#datetime-objects" rel="noreferrer"><code>... | [
{
"answerId": 466376,
"score": 4471,
"isAccepted": true,
"createdAt": "2009-01-21T18:08:52",
"ownerDisplayName": "Patrick Harrington",
"ownerUserId": 41165,
"bodyText": "datetime.strptime parses an input string in the user-specified format into a timezone-naive datetime object: >>> from ... | 1 |
2720014 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2720014/how-to-upgrade-all-python-packages-with-pip | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,720,014 | How to upgrade all Python packages with pip | 2,898 | 2,135,598 | 67 | true | true | [
"python",
"pip",
"pypi"
] | 2010-04-27T09:23:25 | 2026-05-11T05:59:35 | thedjpetersen | false | CC BY-SA 4.0 | 3,452,888 | 324,085 | 29,695 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Is it possible to upgrade all Python packages at one time with pip ? Note : that there is a feature request for this on the official issue tracker. | <p>Is it possible to upgrade all Python packages at one time with <strong><a href="https://pypi.python.org/pypi/pip" rel="noreferrer"><code>pip</code></a></strong>?</p>
<p><strong>Note</strong>: that there is <a href="https://github.com/pypa/pip/issues/4551" rel="noreferrer">a feature request</a> for this on the offici... | [
{
"answerId": 3452888,
"score": 2957,
"isAccepted": true,
"createdAt": "2010-08-10T19:56:49",
"ownerDisplayName": "rbp",
"ownerUserId": 158773,
"bodyText": "There isn't a built-in flag yet. Starting with pip version 22.3, the --outdated and --format=freeze have become mutually exclusive ... | 1 |
72899 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/72899/how-can-i-sort-a-list-of-dictionaries-by-a-value-of-the-dictionary-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 72,899 | How can I sort a list of dictionaries by a value of the dictionary in Python? | 2,859 | 1,492,821 | 22 | true | true | [
"python",
"list",
"sorting",
"dictionary",
"data-structures"
] | 2008-09-16T14:27:47 | 2025-07-23T17:11:37 | masi | false | CC BY-SA 4.0 | 73,050 | 12,398 | 118 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I sort a list of dictionaries by a specific key's value? Given: [{'name': 'Homer', 'age': 39}, {'name': 'Bart', 'age': 10}] When sorted by name , it should become: [{'name': 'Bart', 'age': 10}, {'name': 'Homer', 'age': 39}] | <p>How do I sort a list of dictionaries by a specific key's value? Given:</p>
<pre class="lang-py prettyprint-override"><code>[{'name': 'Homer', 'age': 39}, {'name': 'Bart', 'age': 10}]
</code></pre>
<p>When sorted by <code>name</code>, it should become:</p>
<pre class="lang-py prettyprint-override"><code>[{'name': 'Ba... | [
{
"answerId": 73050,
"score": 3749,
"isAccepted": true,
"createdAt": "2008-09-16T14:39:44",
"ownerDisplayName": "Mario F",
"ownerUserId": 3785,
"bodyText": "The sorted() function takes a key= parameter newlist = sorted(list_to_be_sorted, key=lambda d: d['name']) Alternatively, you can us... | 1 |
990754 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/990754/how-to-leave-exit-deactivate-a-python-virtualenv | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 990,754 | How to leave/exit/deactivate a Python virtualenv | 2,856 | 3,231,537 | 16 | true | true | [
"python",
"virtualenv",
"exit",
"virtualenvwrapper"
] | 2009-06-13T14:15:36 | 2025-08-12T20:00:36 | Apreche | false | CC BY-SA 4.0 | 990,779 | 65,326 | 33,919 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I'm using virtualenv and the virtualenvwrapper. I can switch between virtualenv's just fine using the workon command. me@mymachine:~$ workon env1 (env1)me@mymachine:~$ workon env2 (env2)me@mymachine:~$ workon env1 (env1)me@mymachine:~$ How do I exit all virtual environments and work on my system environment again? Righ... | <p>I'm using virtualenv and the virtualenvwrapper. I can switch between virtualenv's just fine using the <code>workon</code> command.</p>
<pre><code>me@mymachine:~$ workon env1
(env1)me@mymachine:~$ workon env2
(env2)me@mymachine:~$ workon env1
(env1)me@mymachine:~$
</code></pre>
<p>How do I exit all virtual environme... | [
{
"answerId": 990779,
"score": 4559,
"isAccepted": true,
"createdAt": "2009-06-13T14:31:00",
"ownerDisplayName": "Brandon Rhodes",
"ownerUserId": 85360,
"bodyText": "Usually, activating a virtualenv gives you a shell function named: $ deactivate which puts things back to normal. I have j... | 1 |
930397 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/930397/how-do-i-get-the-last-element-of-a-list | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 930,397 | How do I get the last element of a list? | 2,814 | 3,388,910 | 19 | true | true | [
"python",
"list"
] | 2009-05-30T19:28:53 | 2026-05-23T08:12:06 | Janusz | false | CC BY-SA 4.0 | 930,398 | 114,066 | 190,122 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I get the last element of a list in Python? I tried: alist[::-1] but I got ValueError: attempt to assign sequence of size 6 to extended slice of size 5 | <p>How do I get the last element of a list in Python? I tried:</p>
<pre class="lang-py prettyprint-override"><code>alist[::-1]
</code></pre>
<p>but I got</p>
<blockquote>
<p>ValueError: attempt to assign sequence of size 6 to extended slice of size 5</p>
</blockquote>
| [
{
"answerId": 930398,
"score": 4020,
"isAccepted": true,
"createdAt": "2009-05-30T19:29:55",
"ownerDisplayName": "Sasha Chedygov",
"ownerUserId": 104184,
"bodyText": "some_list[-1] is the shortest and most Pythonic. In fact, you can do much more with this syntax. The some_list[-n] syntax... | 1 |
379906 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/379906/how-do-i-parse-a-string-to-a-float-or-int | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 379,906 | How do I parse a string to a float or int? | 2,786 | 4,896,165 | 34 | true | true | [
"python",
"parsing",
"floating-point",
"type-conversion",
"integer"
] | 2008-12-19T01:52:26 | 2026-05-29T15:50:33 | Tristan Havelick | false | CC BY-SA 4.0 | 379,910 | 30,529 | 70,466 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How can I convert an str to a float ? "545.2222" -> 545.2222 Or an str to a int ? "31" -> 31 For the reverse, see Convert integer to string in Python and Converting a float to a string without rounding it . Please instead use How can I read inputs as numbers? to close duplicate questions where OP received a string from... | <p>How can I convert an <code>str</code> to a <code>float</code>?</p>
<pre><code>"545.2222" -> 545.2222
</code></pre>
<p>Or an <code>str</code> to a <code>int</code>?</p>
<pre><code>"31" -> 31
</code></pre>
<hr />
<p><sub>For the reverse, see <a href="https://stackoverflow.com/questions/961632... | [
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"score": 3126,
"isAccepted": true,
"createdAt": "2008-12-19T01:54:51",
"ownerDisplayName": "Harley Holcombe",
"ownerUserId": 1057,
"bodyText": ">>> a = \"545.2222\" >>> float(a) 545.22220000000004 >>> int(float(a)) 545"
}
] | 1 |
4750806 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4750806/how-do-i-install-pip-on-windows | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,750,806 | How do I install pip on Windows? | 2,778 | 3,605,983 | 41 | true | true | [
"python",
"windows",
"pip"
] | 2011-01-20T18:08:59 | 2026-01-27T02:42:43 | mit | false | CC BY-SA 4.0 | 12,476,379 | 362,951 | 11,360 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | pip is a replacement for easy_install . But should I install pip using easy_install on Windows? Is there a better way? | <p><a href="https://pip.pypa.io/en/stable/" rel="noreferrer"><code>pip</code></a> is a replacement for <a href="http://setuptools.readthedocs.io/en/latest/easy_install.html" rel="noreferrer"><code>easy_install</code></a>. But should I install <code>pip</code> using <code>easy_install</code> on Windows? Is there a bette... | [
{
"answerId": 12476379,
"score": 1967,
"isAccepted": true,
"createdAt": "2012-09-18T11:45:33",
"ownerDisplayName": "Colonel Panic",
"ownerUserId": 284795,
"bodyText": "Python 3.4+ and 2.7.9+ Good news! Python 3.4 (released March 2014) and Python 2.7.9 (released December 2014) ship with P... | 1 |
663171 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/663171/how-do-i-get-a-substring-of-a-string-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 663,171 | How do I get a substring of a string in Python? | 2,728 | 4,175,571 | 16 | true | true | [
"python",
"string",
"substring"
] | 2009-03-19T17:29:41 | 2024-09-26T09:43:43 | Joan Venge | true | null | 663,175 | 51,816 | 334,709 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to get a new string from the third character to the end of the string, e.g. myString[2:end] . If omitting the second part means 'to the end', and if you omit the first part, does it start from the start? | <p>I want to get a new string from the third character to the end of the string, e.g. <code>myString[2:end]</code>. If omitting the second part means 'to the end', and if you omit the first part, does it start from the start?</p>
| [
{
"answerId": 663175,
"score": 3835,
"isAccepted": true,
"createdAt": "2009-03-19T17:30:44",
"ownerDisplayName": "Paolo Bergantino",
"ownerUserId": 16417,
"bodyText": ">>> x = \"Hello World!\" >>> x[2:] 'llo World!' >>> x[:2] 'He' >>> x[:-2] 'Hello Worl' >>> x[-2:] 'd!' >>> x[2:-2] 'llo ... | 1 |
5466451 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/5466451/how-do-i-escape-curly-brace-characters-characters-in-a-string-while-using | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 5,466,451 | How do I escape curly-brace ({}) characters characters in a string while using .format? | 2,723 | 1,313,295 | 24 | true | true | [
"python",
"string",
"format",
"string-formatting",
"curly-braces"
] | 2011-03-29T00:04:53 | 2026-04-02T16:13:24 | Schitti | false | CC BY-SA 4.0 | 5,466,478 | 242,670 | 28,459 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Non-working example: print(" \{ Hello \} {0} ".format(42)) Desired output: {Hello} 42 | <p>Non-working example:</p>
<pre><code>print(" \{ Hello \} {0} ".format(42))
</code></pre>
<p>Desired output:</p>
<pre class="lang-none prettyprint-override"><code> {Hello} 42
</code></pre>
| [
{
"answerId": 5466478,
"score": 3573,
"isAccepted": true,
"createdAt": "2011-03-29T00:08:55",
"ownerDisplayName": "Greg Hewgill",
"ownerUserId": 893,
"bodyText": "You need to double the {{ and }} : >>> x = \" {{ Hello }} {0} \" >>> print(x.format(42)) ' { Hello } 42 ' Here's the relevant... | 1 |
1602934 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1602934/check-if-a-given-key-already-exists-in-a-dictionary | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,602,934 | Check if a given key already exists in a dictionary | 2,675 | 7,335,561 | 16 | true | true | [
"python",
"dictionary"
] | 2009-10-21T19:05:09 | 2023-03-07T14:12:21 | Mohan Gulati | false | CC BY-SA 3.0 | 1,602,964 | 112,850 | 28,219 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I wanted to test if a key exists in a dictionary before updating the value for the key. I wrote the following code: if 'key1' in dict.keys(): print "blah" else: print "boo" I think this is not the best way to accomplish this task. Is there a better way to test for a key in the dictionary? | <p>I wanted to test if a key exists in a dictionary before updating the value for the key.
I wrote the following code:</p>
<pre><code>if 'key1' in dict.keys():
print "blah"
else:
print "boo"
</code></pre>
<p>I think this is not the best way to accomplish this task. Is there a better way to test for a key in the d... | [
{
"answerId": 1602964,
"score": 5730,
"isAccepted": true,
"createdAt": "2009-10-21T19:10:21",
"ownerDisplayName": "Chris B.",
"ownerUserId": 9161,
"bodyText": "in tests for the existence of a key in a dict : d = {\"key1\": 10, \"key2\": 23} if \"key1\" in d: print(\"this will execute\") ... | 1 |
68645 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/68645/class-static-variables-and-methods | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 68,645 | Class (static) variables and methods | 2,636 | 1,841,328 | 27 | true | true | [
"python",
"class",
"static",
"class-variables"
] | 2008-09-16T01:46:36 | 2024-01-30T14:39:08 | Andrew Walker | false | CC BY-SA 4.0 | 68,672 | 2,246 | 42,810 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I create class (i.e. static ) variables or methods in Python? | <p>How do I create class (i.e. <a href="https://en.wikipedia.org/wiki/Method_(computer_programming)#Static_methods" rel="noreferrer">static</a>) variables or methods in Python?</p>
| [
{
"answerId": 68672,
"score": 2408,
"isAccepted": true,
"createdAt": "2008-09-16T01:51:06",
"ownerDisplayName": "Blair Conrad",
"ownerUserId": 1199,
"bodyText": "Variables declared inside the class definition, but not inside a method are class or static variables: >>> class MyClass: ... ... | 1 |
6797984 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/6797984/how-do-i-lowercase-a-string-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 6,797,984 | How do I lowercase a string in Python? | 2,587 | 3,221,402 | 10 | true | true | [
"python",
"string",
"uppercase",
"lowercase"
] | 2011-07-23T03:08:53 | 2025-03-19T22:13:07 | Benjamin Didur | false | CC BY-SA 4.0 | 6,797,990 | 858,922 | 26,071 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Is there a way to convert a string to lowercase? "Kilometers" → "kilometers" See How to change a string into uppercase? for the opposite. | <p>Is there a way to convert a string to lowercase?</p>
<pre><code>"Kilometers" → "kilometers"
</code></pre>
<hr />
<p><sub>See <a href="https://stackoverflow.com/questions/9257094">How to change a string into uppercase?</a> for the opposite.</sub></p>
| [
{
"answerId": 6797990,
"score": 3667,
"isAccepted": true,
"createdAt": "2011-07-23T03:09:58",
"ownerDisplayName": "Petar Ivanov",
"ownerUserId": 791998,
"bodyText": "Use str.lower() : \"Kilometer\".lower()"
}
] | 1 |
610883 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/610883/how-can-i-check-if-an-object-has-an-attribute | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 610,883 | How can I check if an object has an attribute? | 2,536 | 1,630,932 | 16 | true | true | [
"python",
"class",
"object",
"attributes",
"attributeerror"
] | 2009-03-04T14:45:59 | 2025-11-22T02:35:49 | Lucas Gabriel Sánchez | false | CC BY-SA 4.0 | 610,893 | 20,601 | 42,035 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I check if an object has some attribute? For example: >>> a = SomeClass() >>> a.property Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: SomeClass instance has no attribute 'property' How do I tell if a has the attribute property before using it? | <p>How do I check if an object has some attribute? For example:</p>
<pre class="lang-none prettyprint-override"><code>>>> a = SomeClass()
>>> a.property
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: SomeClass instance has no attribute 'p... | [
{
"answerId": 610893,
"score": 3523,
"isAccepted": true,
"createdAt": "2009-03-04T14:48:43",
"ownerDisplayName": "Jarret Hardie",
"ownerUserId": 72247,
"bodyText": "Try hasattr() : if hasattr(a, 'property'): a.property See zweiterlinde's answer , which offers good advice about asking for... | 1 |
493386 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/493386/how-to-print-without-a-newline-or-space | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 493,386 | How to print without a newline or space | 2,534 | 2,686,093 | 30 | true | true | [
"python",
"trailing-newline"
] | 2009-01-29T20:58:25 | 2024-05-31T10:28:49 | Andrea Ambu | false | CC BY-SA 4.0 | 493,399 | 21,384 | 39,976 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Consider these examples using print in Python: >>> for i in range(4): print('.') . . . . >>> print('.', '.', '.', '.') . . . . Either a newline or a space is added between each value. How can I avoid that, so that the output is .... instead? In other words, how can I "append" strings to the standard output stream? | <p>Consider these examples using <code>print</code> in Python:</p>
<pre class="lang-py prettyprint-override"><code>>>> for i in range(4): print('.')
.
.
.
.
>>> print('.', '.', '.', '.')
. . . .
</code></pre>
<p>Either a newline or a space is added between each value. How can I avoid that, so that the... | [
{
"answerId": 493399,
"score": 3434,
"isAccepted": true,
"createdAt": "2009-01-29T21:01:43",
"ownerDisplayName": "codelogic",
"ownerUserId": 43427,
"bodyText": "In Python 3, you can use the sep= and end= parameters of the print function: To not add a newline to the end of the string: pri... | 1 |
3061 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/3061/calling-a-function-of-a-module-by-using-its-name-a-string | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 3,061 | Calling a function of a module by using its name (a string) | 2,496 | 1,261,897 | 19 | true | true | [
"python",
"object",
"reflection"
] | 2008-08-06T03:36:08 | 2024-08-23T17:41:09 | ricree | false | CC BY-SA 4.0 | 3,071 | 121 | 36,972 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I call a function, using a string with the function's name? For example: import foo func_name = "bar" call(foo, func_name) # calls foo.bar() | <p>How do I call a function, using a string with the function's name? For example:</p>
<pre><code>import foo
func_name = "bar"
call(foo, func_name) # calls foo.bar()
</code></pre>
| [
{
"answerId": 3071,
"score": 2985,
"isAccepted": true,
"createdAt": "2008-08-06T03:57:16",
"ownerDisplayName": "Patrick Johnmeyer",
"ownerUserId": 363,
"bodyText": "Given a module foo with method bar : import foo bar = getattr(foo, 'bar') result = bar() getattr can similarly be used on c... | 1 |
306400 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/306400/how-can-i-randomly-select-choose-an-item-from-a-list-get-a-random-element | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 306,400 | How can I randomly select (choose) an item from a list (get a random element)? | 2,444 | 2,490,228 | 18 | true | true | [
"python",
"list",
"random"
] | 2008-11-20T18:42:21 | 2023-08-31T22:53:30 | Ray | false | CC BY-SA 4.0 | 306,417 | 4,872 | 194,066 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I retrieve an item at random from the following list? foo = ['a', 'b', 'c', 'd', 'e'] | <p>How do I retrieve an item at random from the following list?</p>
<pre class="lang-py prettyprint-override"><code>foo = ['a', 'b', 'c', 'd', 'e']
</code></pre>
| [
{
"answerId": 306417,
"score": 3546,
"isAccepted": true,
"createdAt": "2008-11-20T18:46:39",
"ownerDisplayName": "Pēteris Caune",
"ownerUserId": 5821,
"bodyText": "Use random.choice() : import random foo = ['a', 'b', 'c', 'd', 'e'] print(random.choice(foo)) For cryptographically secure r... | 1 |
627435 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/627435/how-to-remove-an-element-from-a-list-by-index | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 627,435 | How to remove an element from a list by index | 2,348 | 4,355,248 | 18 | true | true | [
"python",
"list",
"indexing"
] | 2009-03-09T18:16:11 | 2022-08-30T20:15:38 | Joan Venge | false | CC BY-SA 4.0 | 627,453 | 51,816 | 334,709 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I remove an element from a list by index ? I found list.remove() , but this slowly scans the list for an item by value . | <p>How do I remove an element from a list <strong>by index</strong>?</p>
<p>I found <code>list.remove()</code>, but this slowly scans the list for an item <strong>by value</strong>.</p>
| [
{
"answerId": 627453,
"score": 2613,
"isAccepted": true,
"createdAt": "2009-03-09T18:21:24",
"ownerDisplayName": "unbeknown",
"ownerUserId": null,
"bodyText": "Use del and specify the index of the element you want to delete: >>> a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9] >>> del a[-1] >>> a [0, ... | 1 |
13411544 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/13411544/delete-a-column-from-a-pandas-dataframe | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 13,411,544 | Delete a column from a Pandas DataFrame | 2,341 | 4,669,824 | 23 | true | true | [
"python",
"pandas",
"dataframe",
"del"
] | 2012-11-16T06:26:40 | 2025-10-22T10:10:47 | John | false | CC BY-SA 4.0 | 13,485,766 | 390,388 | 43,780 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | To delete a column in a DataFrame, I can successfully use: del df['column_name'] But why can't I use the following? del df.column_name Since it is possible to access the Series via df.column_name , I expected this to work. | <p>To delete a column in a DataFrame, I can successfully use:</p>
<pre class="lang-py prettyprint-override"><code>del df['column_name']
</code></pre>
<p>But why can't I use the following?</p>
<pre class="lang-py prettyprint-override"><code>del df.column_name
</code></pre>
<p>Since it is possible to access the Series vi... | [
{
"answerId": 18145399,
"score": 3756,
"isAccepted": false,
"createdAt": "2013-08-09T11:12:09",
"ownerDisplayName": "LondonRob",
"ownerUserId": 2071807,
"bodyText": "The best way to do this in Pandas is to use drop : df = df.drop('column_name', axis=1) where 1 is the axis number ( 0 for ... | 1 |
1712227 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1712227/how-do-i-get-the-number-of-elements-in-a-list-length-of-a-list-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,712,227 | How do I get the number of elements in a list (length of a list) in Python? | 2,307 | 4,059,753 | 11 | true | true | [
"python",
"list"
] | 2009-11-11T00:30:54 | 2024-07-02T12:05:02 | y2k | false | CC BY-SA 4.0 | 1,712,236 | 206,504 | 66,254 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I get the number of elements in the list items ? items = ["apple", "orange", "banana"] # There are 3 items. | <p>How do I get the number of elements in the list <code>items</code>?</p>
<pre><code>items = ["apple", "orange", "banana"]
# There are 3 items.
</code></pre>
| [
{
"answerId": 1712236,
"score": 2992,
"isAccepted": true,
"createdAt": "2009-11-11T00:33:22",
"ownerDisplayName": "gnud",
"ownerUserId": 27204,
"bodyText": "The len() function can be used with several different types in Python - both built-in types and library types. For example: >>> len... | 1 |
41573587 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/41573587/what-is-the-difference-between-venv-pyvenv-pyenv-virtualenv-virtualenvwrappe | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 41,573,587 | What is the difference between venv, pyvenv, pyenv, virtualenv, virtualenvwrapper, pipenv, etc? | 2,271 | 777,444 | 9 | true | true | [
"python",
"virtualenv",
"virtualenvwrapper",
"pyenv",
"python-venv"
] | 2017-01-10T16:27:43 | 2026-07-03T17:24:14 | Flimm | false | CC BY-SA 4.0 | 41,573,588 | 247,696 | 155,467 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Python 3.3 includes the new package venv in its standard library. What does it do, and how does it differ from all the other packages that match the regex (py)?(v|virtual|pip)?env ? | <p>Python 3.3 includes the new package <code>venv</code> in its standard library. What does it do, and how does it differ from all the other packages that match the regex <code>(py)?(v|virtual|pip)?env</code>?</p>
| [
{
"answerId": 41573588,
"score": 2468,
"isAccepted": true,
"createdAt": "2017-01-10T16:27:43",
"ownerDisplayName": "Flimm",
"ownerUserId": 247696,
"bodyText": "This is my personal recommendation for beginners: start by learning virtualenv and pip , tools which work with both Python 2 and... | 1 |
339007 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/339007/how-do-i-pad-a-string-with-zeros | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 339,007 | How do I pad a string with zeros? | 2,262 | 1,739,821 | 19 | true | true | [
"python",
"string",
"zero-padding"
] | 2008-12-03T22:39:51 | 2026-03-04T22:54:12 | Faisal | false | CC BY-SA 4.0 | 339,013 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I pad a numeric string with zeroes to the left, so that the string has a specific length? | <p>How do I pad a numeric string with zeroes to the left, so that the string has a specific length?</p>
| [
{
"answerId": 339013,
"score": 3517,
"isAccepted": true,
"createdAt": "2008-12-03T22:42:04",
"ownerDisplayName": "Harley Holcombe",
"ownerUserId": 1057,
"bodyText": "To pad strings: >>> print('4'.zfill(3)) 004 >>> print('-4'.zfill(3)) -04 To pad numbers: >>> n = 4 >>> print(f'{n:03}') # ... | 1 |
5844672 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/5844672/delete-an-element-from-a-dictionary | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 5,844,672 | Delete an element from a dictionary | 2,249 | 2,958,095 | 20 | true | true | [
"python",
"dictionary",
"del"
] | 2011-04-30T21:20:57 | 2025-03-24T16:45:10 | richzilla | false | CC BY-SA 4.0 | 5,844,692 | 301,032 | 42,368 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I delete an item from a dictionary in Python? Without modifying the original dictionary, how do I obtain another dictionary with the item removed? See also How can I remove a key from a Python dictionary? for the specific issue of removing an item (by key) that may not already be present. | <ol>
<li>How do I delete an item from a dictionary in Python?</li>
<li><strong>Without</strong> modifying the original dictionary, how do I obtain <strong>another</strong> dictionary with the item removed?</li>
</ol>
<hr />
<p><sub>See also <a href="https://stackoverflow.com/questions/11277432">How can I remove a key f... | [
{
"answerId": 5844692,
"score": 2578,
"isAccepted": true,
"createdAt": "2011-04-30T21:25:39",
"ownerDisplayName": "Greg Hewgill",
"ownerUserId": 893,
"bodyText": "The del statement removes an element: del d[key] Note that this mutates the existing dictionary, so the contents of the dicti... | 1 |
2225038 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2225038/determine-the-type-of-an-object | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,225,038 | Determine the type of an object? | 2,231 | 2,519,455 | 15 | true | true | [
"python",
"dictionary",
"types",
"typeof"
] | 2010-02-08T21:37:20 | 2022-08-29T20:14:36 | Justin Ethier | true | null | 2,225,066 | 101,258 | 134,961 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Is there a simple way to determine if a variable is a list, dictionary, or something else? | <p>Is there a simple way to determine if a variable is a list, dictionary, or something else?</p>
| [
{
"answerId": 2225066,
"score": 2401,
"isAccepted": true,
"createdAt": "2010-02-08T21:40:06",
"ownerDisplayName": "poke",
"ownerUserId": 216074,
"bodyText": "There are two built-in functions that help you identify the type of an object. You can use type() if you need the exact type of an... | 1 |
9573244 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/9573244/how-to-check-if-the-string-is-empty-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 9,573,244 | How to check if the string is empty in Python? | 2,229 | 3,561,301 | 20 | true | true | [
"python",
"string",
"boolean",
"is-empty",
"comparison-operators"
] | 2012-03-05T20:09:23 | 2026-05-02T19:28:18 | Joan Venge | false | CC BY-SA 4.0 | 9,573,259 | 51,816 | 334,709 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Does Python have something like an empty string variable where you can do: if myString == string.empty: Regardless, what's the most elegant way to check for empty string values? I find hard coding "" every time for checking an empty string not as good. | <p>Does Python have something like an empty string variable where you can do:</p>
<pre class="lang-python prettyprint-override"><code>if myString == string.empty:
</code></pre>
<p>Regardless, what's the most elegant way to check for empty string values? I find hard coding <code>""</code> every time for checki... | [
{
"answerId": 9573259,
"score": 3169,
"isAccepted": true,
"createdAt": "2012-03-05T20:10:21",
"ownerDisplayName": "Andrew Clark",
"ownerUserId": 505154,
"bodyText": "Empty strings are \"falsy\" ( python 2 or python 3 reference), which means they are considered false in a Boolean context,... | 1 |
2600191 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2600191/how-do-i-count-the-occurrences-of-a-list-item | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,600,191 | How do I count the occurrences of a list item? | 2,229 | 3,167,734 | 30 | true | true | [
"python",
"list",
"count"
] | 2010-04-08T13:30:00 | 2026-01-01T18:03:01 | weakish | false | CC BY-SA 4.0 | 2,600,208 | 222,893 | 30,310 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Given a single item, how do I count occurrences of it in a list, in Python? A related but different problem is counting occurrences of each different element in a collection, getting a dictionary or list as a histogram result instead of a single integer. For that problem, see Using a dictionary to count the items in a ... | <p>Given a single item, how do I count occurrences of it in a list, in Python?</p>
<hr />
<p><sub>A related but different problem is counting occurrences of <strong>each different element</strong> in a collection, getting a dictionary or list as a histogram result instead of a single integer. For that problem, see <a h... | [
{
"answerId": 2600208,
"score": 2566,
"isAccepted": true,
"createdAt": "2010-04-08T13:31:52",
"ownerDisplayName": "Łukasz",
"ownerUserId": 4999,
"bodyText": "If you only want a single item's count, use the count method: >>> [1, 2, 3, 4, 1, 4, 1].count(1) 3 Important: this is very slow if... | 2 |
9371238 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/9371238/why-is-reading-lines-from-stdin-much-slower-in-c-than-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 9,371,238 | Why is reading lines from stdin much slower in C++ than Python? | 2,203 | 325,429 | 11 | true | true | [
"python",
"c++",
"benchmarking",
"iostream",
"getline"
] | 2012-02-21T02:17:50 | 2024-09-23T13:19:46 | JJC | false | CC BY-SA 4.0 | 9,371,717 | 379,037 | 10,143 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm misunderstanding someth... | <p>I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm misunderstanding som... | [
{
"answerId": 9371717,
"score": 1963,
"isAccepted": true,
"createdAt": "2012-02-21T03:24:19",
"ownerDisplayName": "Vaughn Cato",
"ownerUserId": 951890,
"bodyText": "tl;dr: Because of different default settings in C++ requiring more system calls. By default, cin is synchronized with stdio... | 1 |
493819 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/493819/why-is-it-string-joinlist-instead-of-list-joinstring | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 493,819 | Why is it string.join(list) instead of list.join(string)? | 2,168 | 1,577,880 | 10 | true | true | [
"python",
"string",
"list"
] | 2009-01-29T22:45:13 | 2026-07-10T05:16:54 | Evan Fosmark | false | CC BY-SA 4.0 | 493,842 | 49,701 | 102,727 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | This has always confused me. It seems like this would be nicer: ["Hello", "world"].join("-") Than this: "-".join(["Hello", "world"]) Is there a specific reason it is like this? | <p>This has always confused me. It seems like this would be nicer:</p>
<pre><code>["Hello", "world"].join("-")
</code></pre>
<p>Than this:</p>
<pre><code>"-".join(["Hello", "world"])
</code></pre>
<p>Is there a specific reason it is like this?</p>
| null | 0 |
4706499 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4706499/how-do-i-append-to-a-file | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,706,499 | How do I append to a file? | 2,139 | 2,380,703 | 12 | true | true | [
"python",
"file",
"append"
] | 2011-01-16T16:20:33 | 2022-10-19T00:55:58 | user502039 | false | CC BY-SA 4.0 | 4,706,520 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I append to a file instead of overwriting it? | <p>How do I append to a file instead of overwriting it?</p>
| [
{
"answerId": 4706520,
"score": 3181,
"isAccepted": true,
"createdAt": "2011-01-16T16:24:05",
"ownerDisplayName": "Petter",
"ownerUserId": 116186,
"bodyText": "Set the mode in open() to \"a\" (append) instead of \"w\" (write): with open(\"test.txt\", \"a\") as myfile: myfile.write(\"appe... | 1 |
101754 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/101754/is-there-a-way-to-run-python-on-android | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 101,754 | Is there a way to run Python on Android? | 2,083 | 782,279 | 23 | true | true | [
"android",
"python",
"jython",
"ase",
"android-scripting"
] | 2008-09-19T13:21:12 | 2025-12-08T13:21:21 | Bite code | false | CC BY-SA 4.0 | 8,189,603 | 9,951 | 601,871 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | We are working on an S60 version and this platform has a nice Python API.. However, there is nothing official about Python on Android, but since Jython exists, is there a way to let the snake and the robot work together?? | <p>We are working on an <a href="http://en.wikipedia.org/wiki/S60_%28software_platform%29" rel="noreferrer">S60</a> version and this platform has a nice Python API..</p>
<p>However, there is nothing official about Python on Android, but since <a href="http://en.wikipedia.org/wiki/Jython" rel="noreferrer">Jython</a> ex... | null | 0 |
735975 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/735975/static-methods-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 735,975 | Static methods in Python? | 2,075 | 1,333,424 | 12 | true | true | [
"python",
"static-methods"
] | 2009-04-09T21:23:19 | 2023-01-22T01:42:44 | Joan Venge | false | CC BY-SA 4.0 | 735,978 | 51,816 | 334,709 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Can I define a static method which I can call directly on the class instance? e.g., MyClass.the_static_method() | <p>Can I define a <a href="https://en.wikipedia.org/wiki/Method_(computer_programming)#Static_methods" rel="noreferrer">static method</a> which I can call directly on the class instance? e.g.,</p>
<pre><code>MyClass.the_static_method()
</code></pre>
| [
{
"answerId": 735978,
"score": 2350,
"isAccepted": true,
"createdAt": "2009-04-09T21:24:36",
"ownerDisplayName": "dbr",
"ownerUserId": 745,
"bodyText": "Yep, using the staticmethod decorator: class MyClass(object): @staticmethod def the_static_method(x): print(x) MyClass.the_static_metho... | 1 |
5226311 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/5226311/installing-specific-package-version-with-pip | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 5,226,311 | Installing specific package version with pip | 2,072 | 3,276,835 | 12 | true | true | [
"python",
"mysql",
"pip",
"pypi",
"mysql-python"
] | 2011-03-07T22:58:13 | 2022-12-28T17:21:24 | Joe | false | CC BY-SA 4.0 | 5,226,504 | 306,374 | 27,157 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I am trying to install version 1.2.2 of MySQL_python , using a fresh virtualenv created with the --no-site-packages option. The current version shown in PyPi is 1.2.3 . Is there a way to install the older version? I have tried: pip install MySQL_python==1.2.2 However, when installed, it still shows MySQL_python-1.2.3-p... | <p>I am trying to install version 1.2.2 of <code>MySQL_python</code>, using a fresh virtualenv created with the <code>--no-site-packages</code> option. The current version shown in PyPi is <a href="http://pypi.python.org/pypi/MySQL-python/1.2.3" rel="noreferrer">1.2.3</a>. Is there a way to install the older version? I... | null | 0 |
10660435 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/10660435/how-do-i-split-the-definition-of-a-long-string-over-multiple-lines | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 10,660,435 | How do I split the definition of a long string over multiple lines? | 2,071 | 2,138,353 | 31 | true | true | [
"python",
"string",
"multiline",
"multilinestring"
] | 2012-05-18T22:21:09 | 2025-01-06T20:15:41 | Pablo Mescher | false | CC BY-SA 4.0 | 10,660,443 | 1,231,428 | 27,767 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have a very long query. I would like to split it in several lines in Python. A way to do it in JavaScript would be using several sentences and joining them with a + operator (I know, maybe it's not the most efficient way to do it, but I'm not really concerned about performance in this stage, just code readability). E... | <p>I have a very long query. I would like to split it in several lines in Python. A way to do it in JavaScript would be using several sentences and joining them with a <code>+</code> operator (I know, maybe it's not the most efficient way to do it, but I'm not really concerned about performance in this stage, just code... | [
{
"answerId": 10660443,
"score": 3267,
"isAccepted": true,
"createdAt": "2012-05-18T22:22:54",
"ownerDisplayName": "Levon",
"ownerUserId": 1209279,
"bodyText": "Are you talking about multi-line strings? Easy, use triple quotes to start and end them. s = \"\"\" this is a very long string ... | 1 |
12943819 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/12943819/how-to-prettyprint-a-json-file | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 12,943,819 | How to prettyprint a JSON file? | 2,061 | 2,580,019 | 15 | true | true | [
"python",
"json",
"formatting",
"pretty-print"
] | 2012-10-17T21:38:43 | 2023-10-22T10:53:24 | Colleen | false | CC BY-SA 4.0 | 12,944,035 | 892,387 | 25,957 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I pretty-print a JSON file in Python? | <p>How do I pretty-print a JSON file in Python?</p>
| [
{
"answerId": 12944035,
"score": 3106,
"isAccepted": true,
"createdAt": "2012-10-17T21:54:12",
"ownerDisplayName": "Blender",
"ownerUserId": 464744,
"bodyText": "Use the indent= parameter of json.dump() or json.dumps() to specify how many spaces to indent by: >>> import json >>> your_jso... | 1 |
15943769 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/15943769/how-do-i-get-the-row-count-of-a-pandas-dataframe | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 15,943,769 | How do I get the row count of a Pandas DataFrame? | 2,041 | 4,766,209 | 20 | true | true | [
"python",
"pandas",
"dataframe"
] | 2013-04-11T08:14:08 | 2024-07-16T00:09:16 | yemu | false | CC BY-SA 4.0 | 15,943,975 | 2,006,977 | 28,889 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I get the number of rows of a pandas dataframe df ? | <p>How do I get the number of rows of a pandas dataframe <code>df</code>?</p>
| [
{
"answerId": 15943975,
"score": 3015,
"isAccepted": true,
"createdAt": "2013-04-11T08:24:29",
"ownerDisplayName": "root",
"ownerUserId": 1199589,
"bodyText": "For a dataframe df , one can use any of the following: len(df.index) df.shape[0] df[df.columns[0]].count() (== number of non-NaN... | 1 |
510972 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/510972/getting-the-class-name-of-an-instance | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 510,972 | Getting the class name of an instance | 2,036 | 1,699,238 | 12 | true | true | [
"python",
"introspection",
"instanceof",
"python-datamodel"
] | 2009-02-04T11:37:48 | 2024-08-20T03:18:59 | Dan | false | CC BY-SA 4.0 | 511,059 | 18,909 | 35,883 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I find out the name of the class used to create an instance of an object in Python? I'm not sure if I should use the inspect module or parse the __class__ attribute. | <p>How do I find out the name of the class used to create an instance of an object in Python?</p>
<p>I'm not sure if I should use the <a href="https://docs.python.org/2/library/inspect.html" rel="noreferrer" title="inspect — Inspect live objects"><code>inspect</code></a> module or parse the <code>__class__</code> attri... | [
{
"answerId": 511059,
"score": 2641,
"isAccepted": true,
"createdAt": "2009-02-04T12:02:12",
"ownerDisplayName": "sykloid",
"ownerUserId": 53850,
"bodyText": "Have you tried the __name__ attribute of the class? ie type(x).__name__ will give you the name of the class, which I think is wha... | 1 |
354038 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/354038/how-do-i-check-if-a-string-represents-a-number-float-or-int | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 354,038 | How do I check if a string represents a number (float or int)? | 2,031 | 1,834,888 | 41 | true | true | [
"python",
"casting",
"floating-point",
"type-conversion",
"integer"
] | 2008-12-09T20:03:42 | 2025-12-01T14:37:56 | Daniel Goldberg | false | CC BY-SA 4.0 | 354,130 | 40,115 | 20,776 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I check if a string represents a numeric value in Python? def is_number(s): try: float(s) return True except ValueError: return False The above works, but it seems clunky. Editor's note: If what you are testing comes from user input, it is still a string even if it represents an int or a float . For converting t... | <p>How do I check if a string represents a numeric value in Python?</p>
<pre><code>def is_number(s):
try:
float(s)
return True
except ValueError:
return False
</code></pre>
<p>The above works, but it seems clunky.</p>
<hr />
<p><sub><strong>Editor's note:</strong> If what you are testing... | null | 0 |
152580 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/152580/whats-the-canonical-way-to-check-for-type-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 152,580 | What's the canonical way to check for type in Python? | 2,021 | 1,756,275 | 21 | true | true | [
"python",
"types"
] | 2008-09-30T11:00:10 | 2026-04-22T00:18:01 | Herge | false | CC BY-SA 4.0 | 152,596 | 14,102 | 22,837 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I check if an object is of a given type, or if it inherits from a given type? How do I check if the object o is of type str ? Editor's note : Beginners often wrongly expect a string to already be "a number" – either expecting Python 3.x input to convert type, or expecting that a string like '1' is also simultane... | <p>How do I check if an object is of a given type, or if it inherits from a given type?</p>
<p>How do I check if the object <code>o</code> is of type <code>str</code>?</p>
<hr />
<p><sub><strong>Editor's note</strong>: Beginners often wrongly expect a string to already be "a number" – either expecting Python ... | [
{
"answerId": 152596,
"score": 2364,
"isAccepted": true,
"createdAt": "2008-09-30T11:07:45",
"ownerDisplayName": "Fredrik Johansson",
"ownerUserId": 1163767,
"bodyText": "Use isinstance to check if o is an instance of str or any subclass of str : if isinstance(o, str): To check if the ty... | 1 |
12179271 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/12179271/meaning-of-classmethod-and-staticmethod-for-a-beginner | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 12,179,271 | Meaning of @classmethod and @staticmethod for a beginner | 2,015 | 935,782 | 12 | true | true | [
"python",
"oop",
"static-methods",
"class-method"
] | 2012-08-29T13:37:33 | 2026-02-01T01:44:48 | user1632861 | true | null | 12,179,752 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What do @classmethod and @staticmethod mean in Python, and how are they different? When should I use them, why should I use them, and how should I use them? As far as I understand, @classmethod tells a class that it's a method which should be inherited into subclasses, or... something. However, what's the point of that... | <p>What do <code>@classmethod</code> and <code>@staticmethod</code> mean in Python, and how are they different? <em>When</em> should I use them, <em>why</em> should I use them, and <em>how</em> should I use them?</p>
<p>As far as I understand, <code>@classmethod</code> tells a class that it's a method which should be i... | [
{
"answerId": 12179752,
"score": 3065,
"isAccepted": true,
"createdAt": "2012-08-29T14:03:03",
"ownerDisplayName": "Rostyslav Dzinko",
"ownerUserId": 789649,
"bodyText": "Though classmethod and staticmethod are quite similar, there's a slight difference in usage for both entities: classm... | 1 |
7225900 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/7225900/how-can-i-install-packages-using-pip-according-to-the-requirements-txt-file-from | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 7,225,900 | How can I install packages using pip according to the requirements.txt file from a local directory? | 1,999 | 3,891,230 | 18 | true | true | [
"python",
"pip",
"virtualenv",
"requirements.txt"
] | 2011-08-29T03:53:04 | 2026-01-06T02:15:41 | kakarukeys | false | CC BY-SA 4.0 | 10,429,168 | 496,852 | 24,341 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Here is the problem: I have a requirements.txt file that looks like: BeautifulSoup==3.2.0 Django==1.3 Fabric==1.2.0 Jinja2==2.5.5 PyYAML==3.09 Pygments==1.4 SQLAlchemy==0.7.1 South==0.7.3 amqplib==0.6.1 anyjson==0.3 ... I have a local archive directory containing all the packages + others. I have created a new virtuale... | <p>Here is the problem:</p>
<p>I have a <code>requirements.txt</code> file that looks like:</p>
<pre class="lang-none prettyprint-override"><code>BeautifulSoup==3.2.0
Django==1.3
Fabric==1.2.0
Jinja2==2.5.5
PyYAML==3.09
Pygments==1.4
SQLAlchemy==0.7.1
South==0.7.3
amqplib==0.6.1
anyjson==0.3
...
</code></pre>
<p>I have... | [
{
"answerId": 15593865,
"score": 2651,
"isAccepted": false,
"createdAt": "2013-03-24T00:47:43",
"ownerDisplayName": "Mike Lyons",
"ownerUserId": 710332,
"bodyText": "This works for everyone: pip install -r /path/to/requirements.txt Explanation: -r, --requirement < filename > Install from... | 1 |
1319615 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1319615/how-do-i-declare-custom-exceptions-in-modern-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,319,615 | How do I declare custom exceptions in modern Python? | 1,973 | 1,392,353 | 17 | true | true | [
"python",
"python-3.x",
"exception",
"python-dataclasses",
"pep352"
] | 2009-08-23T21:29:29 | 2025-06-24T15:46:38 | Nelson | false | CC BY-SA 4.0 | 1,319,675 | 144,170 | 30,272 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I declare custom exception classes in modern Python? My primary goal is to follow whatever standard other exception classes have, so that (for instance) any extra string I include in the exception is printed out by whatever tool caught the exception. By "modern Python" I mean something that will run in Python 2.... | <p>How do I declare custom exception classes in modern Python? My primary goal is to follow whatever standard other exception classes have, so that (for instance) any extra string I include in the exception is printed out by whatever tool caught the exception.</p>
<p>By "modern Python" I mean something that w... | [
{
"answerId": 1319675,
"score": 2072,
"isAccepted": true,
"createdAt": "2009-08-23T21:55:23",
"ownerDisplayName": "gahooa",
"ownerUserId": 64004,
"bodyText": "Maybe I missed the question, but why not: class MyException(Exception): pass To override something (or pass extra args), do this:... | 1 |
21530577 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/21530577/fatal-error-python-h-no-such-file-or-directory | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 21,530,577 | fatal error: Python.h: No such file or directory | 1,945 | 1,987,374 | 37 | true | true | [
"python",
"gcc",
"python-c-api"
] | 2014-02-03T15:00:16 | 2025-08-29T16:56:33 | Mohanad Y. | false | CC BY-SA 4.0 | 21,548,557 | 3,266,302 | 19,788 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I am trying to build a shared library using a C extension file but first I have to generate the output file using the command below: gcc -Wall utilsmodule.c -o Utilc After executing the command, I get this error message: > utilsmodule.c:1:20: fatal error: Python.h: No such file or directory compilation terminated. I ha... | <p>I am trying to build a shared library using a C extension file but first I have to generate the output file using the command below:</p>
<pre class="lang-bash prettyprint-override"><code>gcc -Wall utilsmodule.c -o Utilc
</code></pre>
<p>After executing the command, I get this error message:</p>
<pre class="lang-none... | [
{
"answerId": 21530768,
"score": 3620,
"isAccepted": false,
"createdAt": "2014-02-03T15:10:01",
"ownerDisplayName": "wim",
"ownerUserId": 674039,
"bodyText": "Looks like you haven't properly installed the header files and static libraries for python dev. Use your package manager to insta... | 1 |
3996904 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/3996904/generate-random-integers-between-0-and-9 | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 3,996,904 | Generate random integers between 0 and 9 | 1,931 | 3,009,154 | 24 | true | true | [
"python",
"random",
"integer"
] | 2010-10-22T12:48:29 | 2025-03-24T17:05:55 | aneuryzm | false | CC BY-SA 4.0 | 3,996,930 | 257,022 | 65,152 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How can I generate random integers between 0 and 9 (inclusive) in Python? For example, 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 | <p>How can I generate random integers between <code>0</code> and <code>9</code> (inclusive) in Python?</p>
<p>For example, <code>0</code>, <code>1</code>, <code>2</code>, <code>3</code>, <code>4</code>, <code>5</code>, <code>6</code>, <code>7</code>, <code>8</code>, <code>9</code></p>
| [
{
"answerId": 3996930,
"score": 2652,
"isAccepted": true,
"createdAt": "2010-10-22T12:51:31",
"ownerDisplayName": "kovshenin",
"ownerUserId": 24894,
"bodyText": "Try random.randrange : from random import randrange print(randrange(10))"
}
] | 1 |
1301346 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1301346/what-is-the-meaning-of-single-and-double-underscore-before-an-object-name | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,301,346 | What is the meaning of single and double underscore before an object name? | 1,923 | 897,612 | 19 | true | true | [
"python",
"oop",
"naming-conventions",
"identifier"
] | 2009-08-19T17:11:57 | 2025-05-12T10:24:37 | Ram Rachum | false | CC BY-SA 4.0 | 1,301,369 | 76,701 | 89,955 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What do single and double leading underscores before an object's name represent in Python? | <p>What do single and double leading underscores before an object's name represent in Python?</p>
| null | 0 |
14132789 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/14132789/relative-imports-for-the-billionth-time | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 14,132,789 | Relative imports for the billionth time | 1,905 | 783,806 | 17 | true | true | [
"python",
"python-import",
"relative-path",
"python-packaging",
"relative-import"
] | 2013-01-03T03:50:40 | 2025-03-18T06:56:38 | user1881400 | false | CC BY-SA 4.0 | 14,132,912 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I've been here: PEP 328 – Imports: Multi-Line and Absolute/Relative Modules, Packages Python packages: relative imports Python relative import example code does not work Relative imports in Python 2.5 Relative imports in Python Python: Disabling relative import and plenty of URLs that I did not copy, some on SO, some o... | <p>I've been here:</p>
<ul>
<li><em><a href="http://www.python.org/dev/peps/pep-0328/" rel="noreferrer">PEP 328 – Imports: Multi-Line and Absolute/Relative</a></em></li>
<li><em><a href="http://docs.python.org/2/tutorial/modules.html#packages" rel="noreferrer">Modules, Packages</a></em></li>
<li><a href="https://stacko... | [
{
"answerId": 14132912,
"score": 2434,
"isAccepted": true,
"createdAt": "2013-01-03T04:06:37",
"ownerDisplayName": "BrenBarn",
"ownerUserId": 1427416,
"bodyText": "Script vs. Module Here's an explanation. The short version is that there is a big difference between directly running a Pyth... | 1 |
16981921 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/16981921/relative-imports-in-python-3 | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 16,981,921 | Relative imports in Python 3 | 1,892 | 2,222,622 | 36 | true | true | [
"python",
"python-3.x",
"python-import"
] | 2013-06-07T10:26:50 | 2025-05-11T14:17:43 | John Smith Optional | false | CC BY-SA 4.0 | 16,985,066 | 1,126,971 | 25,567 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to import a function from another file in the same directory. Usually, one of the following works: from .mymodule import myfunction from mymodule import myfunction ...but the other one gives me one of these errors: ImportError: attempted relative import with no known parent package ModuleNotFoundError: No module... | <p>I want to import a function from another file in the same directory.</p>
<p>Usually, one of the following works:</p>
<pre><code>from .mymodule import myfunction
</code></pre>
<pre><code>from mymodule import myfunction
</code></pre>
<p>...but the other one gives me one of these errors:</p>
<pre class="lang-none prett... | null | 0 |
12309269 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/12309269/how-do-i-write-json-data-to-a-file | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 12,309,269 | How do I write JSON data to a file? | 1,887 | 3,205,837 | 19 | true | true | [
"python",
"json"
] | 2012-09-06T22:21:21 | 2025-04-27T17:24:47 | user1530318 | false | CC BY-SA 4.0 | 12,309,296 | 1,530,318 | 28,137 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I write JSON data stored in the dictionary data to a file? f = open('data.json', 'wb') f.write(data) This gives the error: TypeError: must be string or buffer, not dict | <p>How do I write JSON data stored in the dictionary <code>data</code> to a file?</p>
<pre><code>f = open('data.json', 'wb')
f.write(data)
</code></pre>
<p>This gives the error:</p>
<blockquote>
<p>TypeError: must be string or buffer, not dict</p>
</blockquote>
| [
{
"answerId": 12309296,
"score": 3355,
"isAccepted": true,
"createdAt": "2012-09-06T22:23:14",
"ownerDisplayName": "phihag",
"ownerUserId": 35070,
"bodyText": "data is a Python dictionary. It needs to be encoded as JSON before writing. Use this for maximum compatibility (Python 2 and 3):... | 1 |
1534210 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1534210/use-a-different-python-version-with-virtualenv | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,534,210 | Use a different Python version with virtualenv | 1,884 | 2,576,920 | 44 | true | true | [
"python",
"virtualenv",
"virtualenvwrapper"
] | 2009-10-07T21:11:22 | 2026-07-03T19:04:35 | Ulf | false | CC BY-SA 4.0 | 1,534,343 | 51,208 | 19,550 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I create a virtual environment for a specified version of Python? | <p>How do I create a virtual environment for a specified version of Python?</p>
| [
{
"answerId": 1534343,
"score": 2069,
"isAccepted": true,
"createdAt": "2009-10-07T21:33:12",
"ownerDisplayName": "Daniel Roseman",
"ownerUserId": 104349,
"bodyText": "NOTE: For Python 3.3+ , see The Aelfinn's answer below. Use the --python (or short -p ) option when creating a virtualen... | 1 |
541390 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/541390/extracting-extension-from-filename | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 541,390 | Extracting extension from filename | 1,879 | 1,690,047 | 33 | true | true | [
"python",
"filenames",
"file-extension"
] | 2009-02-12T14:11:50 | 2025-05-07T12:20:53 | Alex | false | CC BY-SA 4.0 | 541,394 | 85,185 | 45,101 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Is there a function to extract the extension from a filename? | <p>Is there a function to extract the extension from a filename?</p>
| [
{
"answerId": 541394,
"score": 2685,
"isAccepted": true,
"createdAt": "2009-02-12T14:12:46",
"ownerDisplayName": "nosklo",
"ownerUserId": 17160,
"bodyText": "Use os.path.splitext : >>> import os >>> filename, file_extension = os.path.splitext('/path/to/somefile.ext') >>> filename '/path/... | 1 |
67631 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/67631/how-can-i-import-a-module-dynamically-given-the-full-path | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 67,631 | How can I import a module dynamically given the full path? | 1,877 | 1,618,475 | 38 | true | true | [
"python",
"python-import",
"python-module"
] | 2008-09-15T22:30:55 | 2024-02-17T17:55:58 | derfred | false | CC BY-SA 4.0 | 67,692 | 10,286 | 20,201 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I load a Python module given its full path? Note that the file can be anywhere in the filesystem where the user has access rights. See also: How to import a module given its name as string? | <p>How do I load a Python module given its full path?</p>
<p>Note that the file can be anywhere in the filesystem where the user has access rights.</p>
<hr />
<p><sub><strong>See also:</strong> <a href="https://stackoverflow.com/questions/301134">How to import a module given its name as string?</a></sub></p>
| null | 0 |
1557571 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1557571/how-do-i-get-time-of-a-python-programs-execution | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,557,571 | How do I get time of a Python program's execution? | 1,833 | 2,931,696 | 41 | true | true | [
"python",
"time",
"execution-time"
] | 2009-10-12T23:56:47 | 2024-12-11T22:04:58 | john2x | false | CC BY-SA 4.0 | 1,557,584 | 159,685 | 23,952 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have a command line program in Python that takes a while to finish. I want to know the exact time it takes to finish running. I've looked at the timeit module, but it seems it's only for small snippets of code. I want to time the whole program. | <p>I have a command line program in Python that takes a while to finish. I want to know the exact time it takes to finish running.</p>
<p>I've looked at the <code>timeit</code> module, but it seems it's only for small snippets of code. I want to time the whole program.</p>
| [
{
"answerId": 1557584,
"score": 3122,
"isAccepted": true,
"createdAt": "2009-10-13T00:00:53",
"ownerDisplayName": "rogeriopvl",
"ownerUserId": 28388,
"bodyText": "The simplest way in Python: import time start_time = time.time() main() print(\"--- %s seconds ---\" % (time.time() - start_t... | 1 |
5574702 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/5574702/how-do-i-print-to-stderr-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 5,574,702 | How do I print to stderr in Python? | 1,823 | 1,375,535 | 17 | true | true | [
"python",
"printing",
"stderr"
] | 2011-04-07T00:59:10 | 2022-10-03T09:36:11 | wim | false | CC BY-SA 4.0 | 14,981,125 | 674,039 | 370,110 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | There are several ways to write to stderr: print >> sys.stderr, "spam" # Python 2 only. sys.stderr.write("spam\n") os.write(2, b"spam\n") from __future__ import print_function print("spam", file=sys.stderr) What are the differences between these methods? Which method should be preferred? | <p>There are several ways to write to stderr:</p>
<pre><code>print >> sys.stderr, "spam" # Python 2 only.
sys.stderr.write("spam\n")
os.write(2, b"spam\n")
from __future__ import print_function
print("spam", file=sys.stderr)
</code></pre>
<p>What are the differences bet... | null | 0 |
2257441 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/2257441/random-string-generation-with-upper-case-letters-and-digits | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 2,257,441 | Random string generation with upper case letters and digits | 1,823 | 1,550,387 | 36 | true | true | [
"python",
"string",
"random"
] | 2010-02-13T12:23:58 | 2024-08-19T13:20:11 | Hellnar | false | CC BY-SA 4.0 | 2,257,449 | 151,937 | 65,513 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I generate a string of size N, made of numbers and uppercase English letters such as: 6U1S75 4Z4UKK U911K4 | <p>How do I generate a string of size N, made of numbers and uppercase English letters such as:</p>
<ul>
<li>6U1S75</li>
<li>4Z4UKK</li>
<li>U911K4</li>
</ul>
| [
{
"answerId": 2257449,
"score": 3313,
"isAccepted": true,
"createdAt": "2010-02-13T12:26:22",
"ownerDisplayName": "Ignacio Vazquez-Abrams",
"ownerUserId": 20862,
"bodyText": "Answer in one line: ''.join(random.choice(string.ascii_uppercase + string.digits) for _ in range(N)) or even shor... | 1 |
6760685 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/6760685/what-is-the-best-way-of-implementing-a-singleton-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 6,760,685 | What is the best way of implementing a singleton in Python? | 1,812 | 856,747 | 44 | true | true | [
"best-practices",
"python",
"singleton",
"metaclass",
"base-class"
] | 2011-07-20T10:47:57 | 2026-07-13T12:59:40 | theheadofabroom | false | CC BY-SA 4.0 | 73,988,733 | 655,372 | 22,585 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have multiple classes which would become singletons (my use case is for a logger, but this is not important). I do not wish to clutter several classes with added gumph when I can simply inherit or decorate. Best methods: Method 1: A decorator def singleton(class_): instances = {} def getinstance(*args, **kwargs): if ... | <p>I have multiple classes which would become singletons (my use case is for a logger, but this is not important). I do not wish to clutter several classes with added gumph when I can simply inherit or decorate.</p>
<p>Best methods:</p>
<hr />
<h2>Method 1: A decorator</h2>
<pre><code>def singleton(class_):
instanc... | null | 0 |
44834 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/44834/what-does-all-mean-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 44,834 | What does __all__ mean in Python? | 1,809 | 747,521 | 10 | true | true | [
"python",
"syntax",
"namespaces",
"python-import"
] | 2008-09-04T21:28:18 | 2025-03-27T14:46:39 | varikin | false | CC BY-SA 4.0 | 44,842 | 1,794 | 18,483 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I see __all__ in __init__.py files. What does it do? | <p>I see <code>__all__</code> in <code>__init__.py</code> files. What does it do?</p>
| null | 0 |
9622163 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/9622163/save-plot-to-image-file-instead-of-displaying-it | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 9,622,163 | Save plot to image file instead of displaying it | 1,807 | 3,273,678 | 25 | true | true | [
"python",
"matplotlib",
"savefig"
] | 2012-03-08T17:38:10 | 2024-08-14T16:36:23 | Homunculus Reticulli | false | CC BY-SA 4.0 | 9,890,599 | 962,891 | 69,274 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | This displays the figure in a GUI: import matplotlib.pyplot as plt plt.plot([1, 2, 3], [1, 4, 9]) plt.show() But how do I instead save the figure to a file (e.g. foo.png)? | <p>This displays the figure in a GUI:</p>
<pre><code>import matplotlib.pyplot as plt
plt.plot([1, 2, 3], [1, 4, 9])
plt.show()
</code></pre>
<p>But how do I instead save the figure to a file (e.g. foo.png)?</p>
| [
{
"answerId": 9890599,
"score": 2302,
"isAccepted": true,
"createdAt": "2012-03-27T13:35:44",
"ownerDisplayName": "Hooked",
"ownerUserId": 249341,
"bodyText": "When using matplotlib.pyplot.savefig , the file format can be specified by the extension: from matplotlib import pyplot as plt p... | 1 |
11285613 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/11285613/selecting-multiple-columns-in-a-pandas-dataframe | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 11,285,613 | Selecting multiple columns in a Pandas dataframe | 1,801 | 4,276,842 | 22 | true | true | [
"python",
"pandas",
"dataframe",
"select",
"indexing"
] | 2012-07-01T21:03:16 | 2023-11-03T23:33:47 | user1234440 | false | CC BY-SA 4.0 | 11,287,278 | 1,610,626 | 23,777 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I select columns a and b from df , and save them into a new dataframe df1 ? index a b c 1 2 3 4 2 3 4 5 Unsuccessful attempt: df1 = df['a':'b'] df1 = df.ix[:, 'a':'b'] | <p>How do I select columns <code>a</code> and <code>b</code> from <code>df</code>, and save them into a new dataframe <code>df1</code>?</p>
<pre class="lang-none prettyprint-override"><code>index a b c
1 2 3 4
2 3 4 5
</code></pre>
<p>Unsuccessful attempt:</p>
<pre class="lang-py prettyprint-over... | [
{
"answerId": 11287278,
"score": 2743,
"isAccepted": true,
"createdAt": "2012-07-02T02:43:02",
"ownerDisplayName": "ely",
"ownerUserId": 567620,
"bodyText": "The column names (which are strings) cannot be sliced in the manner you tried. Here you have a couple of options. If you know from... | 1 |
209840 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/209840/make-a-dictionary-dict-from-separate-lists-of-keys-and-values | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 209,840 | Make a dictionary (dict) from separate lists of keys and values | 1,798 | 1,425,930 | 22 | true | true | [
"python",
"list",
"dictionary",
"key"
] | 2008-10-16T19:05:47 | 2025-03-25T19:53:42 | Guido | false | CC BY-SA 4.0 | 209,854 | 12,388 | 47,955 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to combine these: keys = ['name', 'age', 'food'] values = ['Monty', 42, 'spam'] into a single dictionary: {'name': 'Monty', 'age': 42, 'food': 'spam'} How can I do this? | <p>I want to combine these:</p>
<pre class="lang-py prettyprint-override"><code>keys = ['name', 'age', 'food']
values = ['Monty', 42, 'spam']
</code></pre>
<p>into a single dictionary:</p>
<pre class="lang-py prettyprint-override"><code>{'name': 'Monty', 'age': 42, 'food': 'spam'}
</code></pre>
<p>How can I do this?</p... | [
{
"answerId": 209854,
"score": 3000,
"isAccepted": true,
"createdAt": "2008-10-16T19:09:05",
"ownerDisplayName": "Dan Lenski",
"ownerUserId": 20789,
"bodyText": "Like this: keys = ['a', 'b', 'c'] values = [1, 2, 3] dictionary = dict(zip(keys, values)) print(dictionary) # {'a': 1, 'b': 2,... | 1 |
678236 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/678236/how-do-i-get-the-filename-without-the-extension-from-a-path-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 678,236 | How do I get the filename without the extension from a path in Python? | 1,793 | 2,410,574 | 33 | true | true | [
"python",
"string",
"path"
] | 2009-03-24T16:41:03 | 2025-05-07T15:31:47 | Joan Venge | false | CC BY-SA 4.0 | 678,242 | 51,816 | 334,709 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I get the filename without the extension from a path in Python? "/path/to/some/file.txt" → "file" | <p>How do I get the filename without the extension from a path in Python?</p>
<pre><code>"/path/to/some/file.txt" → "file"
</code></pre>
| [
{
"answerId": 678242,
"score": 1943,
"isAccepted": true,
"createdAt": "2009-03-24T16:43:15",
"ownerDisplayName": "Geo",
"ownerUserId": 31610,
"bodyText": "Python 3.4+ Use pathlib.Path.stem >>> from pathlib import Path >>> Path(\"/path/to/file.txt\").stem 'file' >>> Path(\"/path/to/file.t... | 1 |
582336 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/582336/how-do-i-profile-a-python-script | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 582,336 | How do I profile a Python script? | 1,762 | 963,808 | 34 | true | true | [
"python",
"performance",
"optimization",
"time-complexity",
"profiling"
] | 2009-02-24T16:01:26 | 2024-07-17T07:12:07 | Chris Lawlor | false | CC BY-SA 4.0 | 582,337 | 21,245 | 49,652 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Project Euler and other coding contests often have a maximum time to run or people boast of how fast their particular solution runs. With Python, sometimes the approaches are somewhat kludgey - i.e., adding timing code to __main__ . What is a good way to profile how long a Python program takes to run? | <p><a href="http://en.wikipedia.org/wiki/Project_Euler" rel="noreferrer">Project Euler</a> and other coding contests often have a maximum time to run or people boast of how fast their particular solution runs. With Python, sometimes the approaches are somewhat kludgey - i.e., adding timing code to <code>__main__</code>... | [
{
"answerId": 582337,
"score": 1829,
"isAccepted": true,
"createdAt": "2009-02-24T16:01:40",
"ownerDisplayName": "Chris Lawlor",
"ownerUserId": 21245,
"bodyText": "Python includes a profiler called cProfile . It not only gives the total running time, but also times each function separate... | 1 |
4260280 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4260280/if-else-in-a-list-comprehension | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,260,280 | if/else in a list comprehension | 1,748 | 2,236,060 | 13 | true | true | [
"python",
"list",
"if-statement",
"list-comprehension"
] | 2010-11-23T19:56:44 | 2025-03-27T14:50:01 | AP257 | false | CC BY-SA 4.0 | 4,260,304 | 267,831 | 95,081 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I convert the following for -loop containing an if / else into a list comprehension? results = [] for x in xs: results.append(f(x) if x is not None else '') It should yield '' if x is None , and otherwise f(x) . I tried: [f(x) for x in xs if x is not None else ''] but it gives a SyntaxError . What is the correct... | <p>How do I convert the following <code>for</code>-loop containing an <code>if</code>/<code>else</code> into a list comprehension?</p>
<pre><code>results = []
for x in xs:
results.append(f(x) if x is not None else '')
</code></pre>
<p>It should yield <code>''</code> if <code>x</code> is <code>None</code>, and other... | [
{
"answerId": 4260304,
"score": 2927,
"isAccepted": true,
"createdAt": "2010-11-23T19:59:17",
"ownerDisplayName": "poke",
"ownerUserId": 216074,
"bodyText": "You can totally do that. It's just an ordering issue: [f(x) if x is not None else '' for x in xs] In general, [f(x) if condition e... | 1 |
944700 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/944700/how-to-check-for-nan-values | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 944,700 | How to check for NaN values | 1,729 | 3,204,757 | 21 | true | true | [
"python",
"math",
"nan"
] | 2009-06-03T13:19:54 | 2024-11-02T11:37:43 | Jack Ha | false | CC BY-SA 4.0 | 944,733 | 80,500 | 21,251 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | float('nan') represents NaN (not a number). But how do I check for it? | <p><code>float('nan')</code> represents NaN (not a number). But how do I check for it?</p>
| [
{
"answerId": 944733,
"score": 2214,
"isAccepted": true,
"createdAt": "2009-06-03T13:24:37",
"ownerDisplayName": "gimel",
"ownerUserId": 6491,
"bodyText": "Use math.isnan : >>> import math >>> x = float('nan') >>> math.isnan(x) True"
}
] | 1 |
4700614 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4700614/how-to-put-the-legend-outside-the-plot | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,700,614 | How to put the legend outside the plot | 1,728 | 2,154,060 | 18 | true | true | [
"python",
"matplotlib",
"seaborn",
"legend"
] | 2011-01-15T16:10:03 | 2026-02-12T22:36:28 | pottigopi | false | CC BY-SA 4.0 | 4,700,674 | 576,840 | 17,289 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I have a series of 20 plots (not subplots) to be made in a single figure. I want the legend to be outside of the box. At the same time, I do not want to change the axes, as the size of the figure gets reduced. I want to keep the legend box outside the plot area (I want the legend to be outside at the right side of the ... | <p>I have a series of 20 plots (not subplots) to be made in a single figure. I want the legend to be outside of the box. At the same time, I do not want to change the axes, as the size of the figure gets reduced.</p>
<ol>
<li>I want to keep the legend box outside the plot area (I want the legend to be outside at the ri... | [
{
"answerId": 4701285,
"score": 2518,
"isAccepted": false,
"createdAt": "2011-01-15T18:12:27",
"ownerDisplayName": "Joe Kington",
"ownerUserId": 325565,
"bodyText": "There are a number of ways to do what you want. To add to what Christian Alis and Navi already said , you can use the bbox... | 2 |
4015417 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/4015417/why-do-python-classes-inherit-object | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 4,015,417 | Why do Python classes inherit object? | 1,717 | 469,076 | 6 | true | true | [
"python",
"class",
"oop",
"object",
"inheritance"
] | 2010-10-25T14:15:26 | 2022-04-09T07:21:43 | tjvr | false | CC BY-SA 4.0 | 45,062,077 | 359,640 | 18,071 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Why does the following class declaration inherit from object ? class MyClass(object): ... | <p>Why does the following class declaration inherit from <code>object</code>?</p>
<pre><code>class MyClass(object):
...
</code></pre>
| [
{
"answerId": 45062077,
"score": 1265,
"isAccepted": true,
"createdAt": "2017-07-12T15:34:59",
"ownerDisplayName": "Dimitris Fasarakis Hilliard",
"ownerUserId": 4952130,
"bodyText": "Is there any reason for a class declaration to inherit from object ? In Python 3, apart from compatibilit... | 1 |
60208 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/60208/replacements-for-switch-statement-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 60,208 | Replacements for switch statement in Python? | 1,716 | 2,361,363 | 44 | true | true | [
"python",
"switch-statement"
] | 2008-09-13T00:36:30 | 2025-02-22T04:31:39 | Michael Schneider | false | CC BY-SA 4.0 | 60,211 | 4,907 | 17,968 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to write a function in Python that returns different fixed values based on the value of an input index. In other languages I would use a switch or case statement, but Python does not appear to have a switch statement. What are the recommended Python solutions in this scenario? | <p>I want to write a function in Python that returns different fixed values based on the value of an input index. </p>
<p>In other languages I would use a <code>switch</code> or <code>case</code> statement, but Python does not appear to have a <code>switch</code> statement. What are the recommended Python solutions ... | [
{
"answerId": 60211,
"score": 2247,
"isAccepted": true,
"createdAt": "2008-09-13T00:38:24",
"ownerDisplayName": "Greg Hewgill",
"ownerUserId": 893,
"bodyText": "Python 3.10 (2021) introduced the match - case statement, which provides a first-class implementation of a \"switch\" for Pytho... | 2 |
931092 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/931092/how-do-i-reverse-a-string-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 931,092 | How do I reverse a string in Python? | 1,714 | 1,756,936 | 14 | true | true | [
"python",
"string"
] | 2009-05-31T02:10:10 | 2023-12-23T07:11:28 | oneself | false | CC BY-SA 4.0 | 931,095 | 9,435 | 40,949 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | There is no built in reverse method for Python's str object. How can I reverse a string? | <p>There is no built in <code>reverse</code> method for Python's <code>str</code> object. How can I reverse a string?</p>
| [
{
"answerId": 931095,
"score": 3168,
"isAccepted": true,
"createdAt": "2009-05-31T02:11:46",
"ownerDisplayName": "Paolo Bergantino",
"ownerUserId": 16417,
"bodyText": "Using slicing : >>> 'hello world'[::-1] 'dlrow olleh' Slice notation takes the form [start:stop:step] . In this case, we... | 1 |
8933237 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/8933237/how-do-i-check-if-a-directory-exists-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 8,933,237 | How do I check if a directory exists in Python? | 1,682 | 1,795,935 | 16 | true | true | [
"python",
"directory"
] | 2012-01-19T21:03:20 | 2026-05-12T09:45:02 | David542 | false | CC BY-SA 4.0 | 8,933,290 | 651,174 | 112,952 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I check if a directory exists in Python? | <p>How do I check if a directory exists in Python?</p>
| [
{
"answerId": 8933290,
"score": 2445,
"isAccepted": true,
"createdAt": "2012-01-19T21:07:25",
"ownerDisplayName": "phihag",
"ownerUserId": 35070,
"bodyText": "Use os.path.isdir for directories only: >>> import os >>> os.path.isdir('new_folder') True Use os.path.exists for both files and ... | 1 |
1471994 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1471994/what-is-setup-py | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,471,994 | What is setup.py? | 1,657 | 1,308,666 | 10 | true | true | [
"python",
"pypi",
"setup.py",
"python-packaging"
] | 2009-09-24T14:16:52 | 2025-09-16T06:39:45 | Software Enthusiastic | false | CC BY-SA 4.0 | 1,472,014 | 97,526 | 26,693 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What is setup.py and how can it be configured or used? | <p>What is <code>setup.py</code> and how can it be configured or used?</p>
| [
{
"answerId": 1472014,
"score": 1229,
"isAccepted": true,
"createdAt": "2009-09-24T14:19:35",
"ownerDisplayName": "Silfverstrom",
"ownerUserId": 54736,
"bodyText": "setup.py is a Python file, the presence of which is an indication that the module/package you are about to install has like... | 1 |
7943751 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/7943751/what-is-the-python-3-equivalent-of-python-m-simplehttpserver | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 7,943,751 | What is the Python 3 equivalent of "python -m SimpleHTTPServer" | 1,653 | 851,729 | 7 | true | true | [
"python",
"python-3.x",
"httpserver",
"simplehttpserver"
] | 2011-10-30T07:22:49 | 2022-02-22T06:55:42 | ryanbraganza | false | CC BY-SA 4.0 | 7,943,768 | 845,948 | 17,263 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What is the Python 3 equivalent of python -m SimpleHTTPServer ? | <p>What is the Python 3 equivalent of <code>python -m SimpleHTTPServer</code>?</p>
| [
{
"answerId": 7943768,
"score": 2307,
"isAccepted": true,
"createdAt": "2011-10-30T07:28:58",
"ownerDisplayName": "Petr Viktorin",
"ownerUserId": 99057,
"bodyText": "From the docs : The SimpleHTTPServer module has been merged into http.server in Python 3.0. The 2to3 tool will automatical... | 1 |
230751 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/230751/how-can-i-flush-the-output-of-the-print-function | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 230,751 | How can I flush the output of the print function? | 1,646 | 1,209,293 | 14 | true | true | [
"python",
"printing",
"flush",
"output-buffering"
] | 2008-10-23T17:59:39 | 2024-03-21T09:13:14 | Walter Nissen | false | CC BY-SA 4.0 | 230,774 | 8,835 | 17,227 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I force Python's print function to flush the buffered output to the screen? See also: Disable output buffering if the goal is to change the buffering behaviour generally. This question is about explicitly flushing output after a specific print call, even though output is still being buffered. For duplicate close... | <p>How do I force Python's <code>print</code> function to flush the buffered output to the screen?</p>
<hr />
<p><sub><strong>See also:</strong> <a href="https://stackoverflow.com/questions/107705">Disable output buffering</a> if the goal is to change the buffering behaviour generally. This question is about explicitly... | [
{
"answerId": 230774,
"score": 1959,
"isAccepted": true,
"createdAt": "2008-10-23T18:04:59",
"ownerDisplayName": "CesarB",
"ownerUserId": 28258,
"bodyText": "In Python 3, print can take an optional flush argument: print(\"Hello, World!\", flush=True) In Python 2, after calling print , do... | 1 |
3702675 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/3702675/catch-and-print-full-python-exception-traceback-without-halting-exiting-the-prog | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 3,702,675 | Catch and print full Python exception traceback without halting/exiting the program | 1,626 | 1,860,013 | 19 | true | true | [
"python",
"exception",
"try-catch",
"traceback"
] | 2010-09-13T17:03:30 | 2024-12-05T09:33:21 | chriscauley | false | CC BY-SA 4.0 | 16,946,886 | 266,564 | 21,681 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I want to catch and log exceptions without exiting, e.g., try: do_stuff() except Exception as err: print(Exception, err) # I want to print the entire traceback here, # not just the exception name and details I want to print the exact same output that is printed when the exception is raised without the try/except interc... | <p>I want to catch and log exceptions without exiting, e.g.,</p>
<pre><code>try:
do_stuff()
except Exception as err:
print(Exception, err)
# I want to print the entire traceback here,
# not just the exception name and details
</code></pre>
<p>I want to print the exact same output that is printed when th... | [
{
"answerId": 3702847,
"score": 1530,
"isAccepted": false,
"createdAt": "2010-09-13T17:27:26",
"ownerDisplayName": "volting",
"ownerUserId": 252701,
"bodyText": "traceback.format_exc() will yield more info if that's what you want. import traceback def do_stuff(): raise Exception(\"test e... | 1 |
1747817 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1747817/create-a-dictionary-with-comprehension | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,747,817 | Create a dictionary with comprehension | 1,614 | 1,254,758 | 17 | true | true | [
"python",
"dictionary",
"list-comprehension",
"dictionary-comprehension"
] | 2009-11-17T10:07:53 | 2023-09-12T13:26:51 | flybywire | false | CC BY-SA 4.0 | 1,747,827 | 63,051 | 277,632 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | Can I use list comprehension syntax to create a dictionary? For example, by iterating over pairs of keys and values: d = {... for k, v in zip(keys, values)} | <p>Can I use list comprehension syntax to create a dictionary?</p>
<p>For example, by iterating over pairs of keys and values:</p>
<pre><code>d = {... for k, v in zip(keys, values)}
</code></pre>
| [
{
"answerId": 1747827,
"score": 2368,
"isAccepted": true,
"createdAt": "2009-11-17T10:09:32",
"ownerDisplayName": "fortran",
"ownerUserId": 106979,
"bodyText": "Use a dict comprehension (Python 2.7 and later): {key: value for key, value in zip(keys, values)} Alternatively, use the dict c... | 1 |
3394835 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/3394835/use-of-args-and-kwargs | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 3,394,835 | Use of *args and **kwargs | 1,599 | 995,807 | 11 | true | true | [
"python",
"args",
"keyword-argument"
] | 2010-08-03T08:28:07 | 2021-07-29T20:26:33 | MacPython | true | null | 3,394,898 | 337,247 | 18,499 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | So I have difficulty with the concept of *args and **kwargs . So far I have learned that: *args = list of arguments - as positional arguments **kwargs = dictionary - whose keys become separate keyword arguments and the values become values of these arguments. I don't understand what programming task this would be helpf... | <p>So I have difficulty with the concept of <code>*args</code> and <code>**kwargs</code>.</p>
<p>So far I have learned that:</p>
<ul>
<li><code>*args</code> = list of arguments - as positional arguments</li>
<li><code>**kwargs</code> = dictionary - whose keys become separate keyword arguments and the values become va... | [
{
"answerId": 3394898,
"score": 1832,
"isAccepted": true,
"createdAt": "2010-08-03T08:38:45",
"ownerDisplayName": "David Webb",
"ownerUserId": 3171,
"bodyText": "The syntax is the * and ** . The names *args and **kwargs are only by convention but there's no hard requirement to use them. ... | 1 |
961632 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/961632/convert-integer-to-string-in-python | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 961,632 | Convert integer to string in Python | 1,596 | 3,896,982 | 14 | true | true | [
"python",
"string",
"integer"
] | 2009-06-07T10:22:38 | 2024-12-17T14:48:15 | Hick | false | CC BY-SA 4.0 | 961,638 | 105,167 | 36,624 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I convert an integer to a string? 42 ⟶ "42" For the reverse, see How do I parse a string to a float or int? . Floats can be handled similarly, but handling the decimal points can be tricky because floating-point values are not precise . See Converting a float to a string without rounding it for more specific adv... | <p>How do I convert an integer to a string?</p>
<pre><code>42 ⟶ "42"
</code></pre>
<hr />
<p><sub>For the reverse, see <a href="https://stackoverflow.com/questions/379906/">How do I parse a string to a float or int?</a>. Floats can be handled similarly, but handling the decimal points can be tricky becaus... | [
{
"answerId": 961638,
"score": 2358,
"isAccepted": true,
"createdAt": "2009-06-07T10:24:15",
"ownerDisplayName": "Bastien Léonard",
"ownerUserId": 88851,
"bodyText": ">>> str(42) '42' >>> int('42') 42 Links to the documentation: int() str() str(x) converts any object x to a string by cal... | 1 |
9001509 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/9001509/how-do-i-sort-a-dictionary-by-key | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 9,001,509 | How do I sort a dictionary by key? | 1,587 | 2,450,419 | 33 | true | true | [
"python",
"sorting",
"dictionary"
] | 2012-01-25T10:54:29 | 2026-03-09T08:42:57 | Antony | false | CC BY-SA 4.0 | 9,001,529 | 1,069,533 | 16,497 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | How do I sort a dictionary by its keys? Example input: {2:3, 1:89, 4:5, 3:0} Desired output: {1:89, 2:3, 3:0, 4:5} | <p>How do I sort a dictionary by its keys?</p>
<p>Example input:</p>
<pre><code>{2:3, 1:89, 4:5, 3:0}
</code></pre>
<p>Desired output:</p>
<pre><code>{1:89, 2:3, 3:0, 4:5}
</code></pre>
| [
{
"answerId": 9001529,
"score": 1325,
"isAccepted": true,
"createdAt": "2012-01-25T10:56:30",
"ownerDisplayName": "NPE",
"ownerUserId": 367273,
"bodyText": "Note: for Python 3.7+, see this answer Standard Python dictionaries are unordered (until Python 3.7). Even if you sorted the (key,v... | 1 |
15891038 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/15891038/change-column-type-in-pandas | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 15,891,038 | Change column type in pandas | 1,585 | 4,252,751 | 16 | true | true | [
"python",
"pandas",
"dataframe",
"types",
"type-conversion"
] | 2013-04-08T23:53:30 | 2024-07-09T21:49:17 | user1642513 | false | CC BY-SA 4.0 | 28,648,923 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | I created a DataFrame from a list of lists: table = [ ['a', '1.2', '4.2' ], ['b', '70', '0.03'], ['x', '5', '0' ], ] df = pd.DataFrame(table) How do I convert the columns to specific types? In this case, I want to convert columns 2 and 3 into floats. Is there a way to specify the types while converting the list to Data... | <p>I created a DataFrame from a list of lists:</p>
<pre class="lang-py prettyprint-override"><code>table = [
['a', '1.2', '4.2' ],
['b', '70', '0.03'],
['x', '5', '0' ],
]
df = pd.DataFrame(table)
</code></pre>
<p>How do I convert the columns to specific types? In this case, I want to convert co... | [
{
"answerId": 28648923,
"score": 2642,
"isAccepted": true,
"createdAt": "2015-02-21T17:37:02",
"ownerDisplayName": "Alex Riley",
"ownerUserId": 3923281,
"bodyText": "You have four main options for converting types in pandas: to_numeric() - provides functionality to safely convert non-num... | 1 |
1549801 | question | stackoverflow | 2026-08-03T01:37:29 | null | null | null | null | null | https://stackoverflow.com/questions/1549801/what-are-the-differences-between-type-and-isinstance | OcN7A9CDxbrWVwaw5 | unPv1LuxmpaTYkIgE | 1,549,801 | What are the differences between type() and isinstance()? | 1,577 | 922,236 | 8 | true | true | [
"python",
"oop",
"inheritance",
"types"
] | 2009-10-11T03:50:54 | 2023-09-13T08:33:28 | abbot | true | null | 1,549,854 | 4,001 | 27,986 | null | null | null | null | null | null | null | null | null | null | null | null | null | null | null | What are the differences between these two code snippets? Using type : import types if type(a) is types.DictType: do_something() if type(b) in types.StringTypes: do_something_else() Using isinstance : if isinstance(a, dict): do_something() if isinstance(b, str) or isinstance(b, unicode): do_something_else() | <p>What are the differences between these two code snippets?</p>
<p>Using <a href="https://docs.python.org/3/library/functions.html#type" rel="noreferrer"><code>type</code></a>:</p>
<pre><code>import types
if type(a) is types.DictType:
do_something()
if type(b) in types.StringTypes:
do_something_else()
</code>... | [
{
"answerId": 1549854,
"score": 1557,
"isAccepted": true,
"createdAt": "2009-10-11T04:31:57",
"ownerDisplayName": "Alex Martelli",
"ownerUserId": 95810,
"bodyText": "To summarize the contents of other (already good!) answers, isinstance caters for inheritance (an instance of a derived cl... | 1 |
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