Instruction:
Can you write a function in Python 3 where it
finds a view function in a module.

Response:
def find_view_function(module_name, function_name, fallback_app=None, fallback_template=None, verify_decorator=True):
    '''
    Finds a view function, class-based view, or template view.
    Raises ViewDoesNotExist if not found.
    '''
    dmp = apps.get_app_config('django_mako_plus')

    # I'm first calling find_spec first here beacuse I don't want import_module in
    # a try/except -- there are lots of reasons that importing can fail, and I just want to
    # know whether the file actually exists.  find_spec raises AttributeError if not found.
    try:
        spec = find_spec(module_name)
    except ValueError:
        spec = None
    if spec is None:
        # no view module, so create a view function that directly renders the template
        try:
            return create_view_for_template(fallback_app, fallback_template)
        except TemplateDoesNotExist as e:
            raise ViewDoesNotExist('view module {} not found, and fallback template {} could not be loaded ({})'.format(module_name, fallback_template, e))

    # load the module and function
    try:
        module = import_module(module_name)
        func = getattr(module, function_name)
        func.view_type = 'function'
    except ImportError as e:
        raise ViewDoesNotExist('module "{}" could not be imported: {}'.format(module_name, e))
    except AttributeError as e:
        raise ViewDoesNotExist('module "{}" found successfully, but "{}" was not found: {}'.format(module_name, function_name, e))

    # if class-based view, call as_view() to get a view function to it
    if inspect.isclass(func) and issubclass(func, View):
        func = func.as_view()
        func.view_type = 'class'

    # if regular view function, check the decorator
    elif verify_decorator and not view_function.is_decorated(func):
        raise ViewDoesNotExist("view {}.{} was found successfully, but it must be decorated with @view_function or be a subclass of django.views.generic.View.".format(module_name, function_name))

    # attach a converter to the view function
    if dmp.options['PARAMETER_CONVERTER'] is not None:
        try:
            converter = import_qualified(dmp.options['PARAMETER_CONVERTER'])(func)
            setattr(func, CONVERTER_ATTRIBUTE_NAME, converter)
        except ImportError as e:
            raise ImproperlyConfigured('Cannot find PARAMETER_CONVERTER: {}'.format(str(e)))

    # return the function/class
    return func


Instruction:
Write a Python 3 function for
creating a view function for templates.

Response:
def create_view_for_template(app_name, template_name):
    '''
    Creates a view function for templates (used whe a view.py file doesn't exist but the .html does)
    Raises TemplateDoesNotExist if the template doesn't exist.
    '''
    # ensure the template exists
    apps.get_app_config('django_mako_plus').engine.get_template_loader(app_name).get_template(template_name)
    # create the view function
    def template_view(request, *args, **kwargs):
        # not caching the template object (getting it each time) because Mako has its own cache
        dmp = apps.get_app_config('django_mako_plus')
        template = dmp.engine.get_template_loader(app_name).get_template(template_name)
        return template.render_to_response(request=request, context=kwargs)
    template_view.view_type = 'template'
    return template_view


Instruction:
Can you tell what is the following Python 3 function doing
def iter_related(self):
        '''
        Generator function that iterates this object's related providers,
        which includes this provider.
        '''
        for tpl in self.provider_run.templates:
            yield tpl.providers[self.index]

Response: Generator function that iterates this object s related providers and returns each of them


Instruction:
Can you generate the documentation for the following Python 3 function
def get_cache_item(self):
        '''Gets the cached item. Raises AttributeError if it hasn't been set.'''
        if settings.DEBUG:
            raise AttributeError('Caching disabled in DEBUG mode')
        return getattr(self.template, self.options['template_cache_key'])

Response: Gets the cached item. Raises AttributeError if it hasn t been set.


Instruction:
Can you generate a brief explanation for the following Python 3 code
def flatten(*args):
    '''Generator that recursively flattens embedded lists, tuples, etc.'''
    for arg in args:
        if isinstance(arg, collections.Iterable) and not isinstance(arg, (str, bytes)):
            yield from flatten(*arg)
        else:
            yield arg

Response: Generator that recursively flattens embedded lists tuples etc.


Instruction:
How would you implement a function in Python 3 that
calculates the CRC checksum for a file.

Response:
def crc32(filename):
    '''
    Calculates the CRC checksum for a file.
    Using CRC32 because security isn't the issue and don't need perfect noncollisions.
    We just need to know if a file has changed.

    On my machine, crc32 was 20 times faster than any hashlib algorithm,
    including blake and md5 algorithms.
    '''
    result = 0
    with open(filename, 'rb') as fin:
        while True:
            chunk = fin.read(48)
            if len(chunk) == 0:
                break
            result = zlib.crc32(chunk, result)
    return result


Instruction:
Can you generate a brief explanation for the following Python 3 code
def compile_mako_files(self, app_config):
        '''Compiles the Mako templates within the apps of this system'''
        # go through the files in the templates, scripts, and styles directories
        for subdir_name in self.SEARCH_DIRS:
            subdir = subdir_name.format(
                app_path=app_config.path,
                app_name=app_config.name,
            )

            def recurse_path(path):
                self.message('searching for Mako templates in {}'.format(path), 1)
                if os.path.exists(path):
                    for filename in os.listdir(path):
                        filepath = os.path.join(path, filename)
                        _, ext = os.path.splitext(filename)
                        if filename.startswith('__'):  # __dmpcache__, __pycache__
                            continue

                        elif os.path.isdir(filepath):
                            recurse_path(filepath)

                        elif ext.lower() in ( '.htm', '.html', '.mako' ):
                            # create the template object, which creates the compiled .py file
                            self.message('compiling {}'.format(filepath), 2)
                            try:
                                get_template_for_path(filepath)
                            except TemplateSyntaxError:
                                if not self.options.get('ignore_template_errors'):
                                    raise

            recurse_path(subdir)

Response: Compiles the Mako templates within the apps of this system


Instruction:
Here you have a function in Python 3, explain what it does
def from_string(self, template_code):
        '''
        Compiles a template from the given string.
        This is one of the required methods of Django template engines.
        '''
        dmp = apps.get_app_config('django_mako_plus')
        mako_template = Template(template_code, imports=dmp.template_imports, input_encoding=dmp.options['DEFAULT_TEMPLATE_ENCODING'])
        return MakoTemplateAdapter(mako_template)

Response: Returns a MakoTemplateAdapter instance from the given string.


Instruction:
Write a Python 3 script for
returning a template object from the pattern app_name / template. html.

Response:
def get_template(self, template_name):
        '''
        Retrieves a template object from the pattern "app_name/template.html".
        This is one of the required methods of Django template engines.

        Because DMP templates are always app-specific (Django only searches
        a global set of directories), the template_name MUST be in the format:
        "app_name/template.html" (even on Windows).  DMP splits the template_name
        string on the slash to get the app name and template name.

        Template rendering can be limited to a specific def/block within the template
        by specifying `#def_name`, e.g. `myapp/mytemplate.html#myblockname`.
        '''
        dmp = apps.get_app_config('django_mako_plus')
        match = RE_TEMPLATE_NAME.match(template_name)
        if match is None or match.group(1) is None or match.group(3) is None:
            raise TemplateDoesNotExist('Invalid template_name format for a DMP template.  This method requires that the template name be in app_name/template.html format (separated by slash).')
        if not dmp.is_registered_app(match.group(1)):
            raise TemplateDoesNotExist('Not a DMP app, so deferring to other template engines for this template')
        return self.get_template_loader(match.group(1)).get_template(match.group(3), def_name=match.group(5))


Instruction:
Implement a function in Python 3 to
return a template loader object for the given app and subdirectory.

Response:
def get_template_loader(self, app, subdir='templates', create=False):
        '''
        Returns a template loader object for the given app name in the given subdir.
        For example, get_template_loader('homepage', 'styles') will return
        a loader for the styles/ directory in the homepage app.

        The app parameter can be either an app name or an AppConfig instance.
        The subdir parameter is normally 'templates', 'scripts', or 'styles',
        but it can be any subdirectory name of the given app.

        Normally, you should not have to call this method.  Django automatically
        generates two shortcut functions for every DMP-registered apps,
        and these shortcut functions are the preferred way to render templates.

        This method is useful when you want a custom template loader to a directory
        that does not conform to the app_dir/templates/* pattern.

        If the loader is not found in the DMP cache, one of two things occur:
          1. If create=True, it is created automatically and returned.  This overrides
             the need to register the app as a DMP app.
          2. If create=False, a TemplateDoesNotExist is raised.  This is the default
             behavior.
        '''
        # ensure we have an AppConfig
        if app is None:
            raise TemplateDoesNotExist("Cannot locate loader when app is None")
        if not isinstance(app, AppConfig):
            app = apps.get_app_config(app)

        # get the loader with the path of this app+subdir
        path = os.path.join(app.path, subdir)

        # if create=False, the loader must already exist in the cache
        if not create:
            dmp = apps.get_app_config('django_mako_plus')
            if not dmp.is_registered_app(app):
                raise ValueError("{} is not registered with DMP [hint: check urls.py for include('django_mako_plus.urls')].".format(app))

        # return the template by path
        return self.get_template_loader_for_path(path, use_cache=True)


Instruction:
Write a Python 3 function that can
return a template loader object for the given path.

Response:
def get_template_loader_for_path(self, path, use_cache=True):
        '''
        Returns a template loader object for the given directory path.
        For example, get_template_loader('/var/mytemplates/') will return
        a loader for that specific directory.

        Normally, you should not have to call this method.  Django automatically
        adds request.dmp.render() and request.dmp.render_to_string() on each
        request.

        This method is useful when you want a custom template loader for a specific
        directory that may be outside your project directory or that is otherwise
        not contained in a normal Django app.  If the directory is inside an app,
        call get_template_loader() instead.

        Unless use_cache=False, this method caches template loaders in the DMP
        cache for later use.
        '''
        # get from the cache if we are able
        if use_cache:
            try:
                return self.template_loaders[path]
            except KeyError:
                pass  # not there, so we'll create

        # create the loader
        loader = MakoTemplateLoader(path, None)

        # cache if we are allowed
        if use_cache:
            self.template_loaders[path] = loader

        # return
        return loader


Instruction:
Create a Python 3 function to
trigger by the converter_function decorator

Response:
def _register_converter(cls, conv_func, conv_type):
        '''Triggered by the @converter_function decorator'''
        cls.converters.append(ConverterFunctionInfo(conv_func, conv_type, len(cls.converters)))
        cls._sort_converters()


Instruction:
Here you have a function in Python 3, explain what it does
def _sort_converters(cls, app_ready=False):
        '''Sorts the converter functions'''
        # app_ready is True when called from DMP's AppConfig.ready()
        # we can't sort before then because models aren't ready
        cls._sorting_enabled = cls._sorting_enabled or app_ready
        if cls._sorting_enabled:
            for converter in cls.converters:
                converter.prepare_sort_key()
            cls.converters.sort(key=attrgetter('sort_key'))

Response: Sorts the converter functions


Instruction:
Can you tell what is the following Python 3 function doing
def convert_parameters(self, request, *args, **kwargs):
        '''
        Iterates the urlparams and converts them according to the
        type hints in the current view function.  This is the primary
        function of the class.
        '''
        args = list(args)
        urlparam_i = 0

        parameters = self.view_parameters.get(request.method.lower()) or self.view_parameters.get(None)
        if parameters is not None:
            # add urlparams into the arguments and convert the values
            for parameter_i, parameter in enumerate(parameters):
                # skip request object, *args, **kwargs
                if parameter_i == 0 or parameter.kind is inspect.Parameter.VAR_POSITIONAL or parameter.kind is inspect.Parameter.VAR_KEYWORD:
                    pass
                # value in kwargs?
                elif parameter.name in kwargs:
                    kwargs[parameter.name] = self.convert_value(kwargs[parameter.name], parameter, request)
                # value in args?
                elif parameter_i - 1 < len(args):
                    args[parameter_i - 1] = self.convert_value(args[parameter_i - 1], parameter, request)
                # urlparam value?
                elif urlparam_i < len(request.dmp.urlparams):
                    kwargs[parameter.name] = self.convert_value(request.dmp.urlparams[urlparam_i], parameter, request)
                    urlparam_i += 1
                # can we assign a default value?
                elif parameter.default is not inspect.Parameter.empty:
                    kwargs[parameter.name] = self.convert_value(parameter.default, parameter, request)
                # fallback is None
                else:
                    kwargs[parameter.name] = self.convert_value(None, parameter, request)

        return args, kwargs

Response: This function converts the urlparams of the current view function into the arguments and kwargs.


Instruction:
Create a Python 3 function to
convert a value from the request object to the parameter object.

Response:
def convert_value(self, value, parameter, request):
        '''
        Converts a parameter value in the view function call.

            value:      value from request.dmp.urlparams to convert
                        The value will always be a string, even if empty '' (never None).

            parameter:  an instance of django_mako_plus.ViewParameter that holds this parameter's
                        name, type, position, etc.

            request:    the current request object.

        "converter functions" register with this class using the @parameter_converter
        decorator.  See converters.py for the built-in converters.

        This function goes through the list of registered converter functions,
        selects the most-specific one that matches the parameter.type, and
        calls it to convert the value.

        If the converter function raises a ValueError, it is caught and
        switched to an Http404 to tell the browser that the requested URL
        doesn't resolve to a page.

        Other useful exceptions that converter functions can raise are:

            Any extension of BaseRedirectException (RedirectException,
                InternalRedirectException, JavascriptRedirectException, ...)
            Http404: returns a Django Http404 response
        '''
        try:
            # we don't convert anything without type hints
            if parameter.type is inspect.Parameter.empty:
                if log.isEnabledFor(logging.DEBUG):
                    log.debug('skipping conversion of parameter `%s` because it has no type hint', parameter.name)
                return value

            # find the converter method for this type
            # I'm iterating through the list to find the most specific match first
            # The list is sorted by specificity so subclasses come before their superclasses
            for ci in self.converters:
                if issubclass(parameter.type, ci.convert_type):
                    if log.isEnabledFor(logging.DEBUG):
                        log.debug('converting parameter `%s` using %s', parameter.name, ci.convert_func)
                    return ci.convert_func(value, parameter)

            # if we get here, there wasn't a converter or this type
            raise ImproperlyConfigured(message='No parameter converter exists for type: {}. Do you need to add an @parameter_converter function for the type?'.format(parameter.type))

        except (BaseRedirectException, Http404):
            log.info('Exception raised during conversion of parameter %s (%s): %s', parameter.position, parameter.name, e)
            raise   # allow these to pass through to the router

        except ValueError as e:
            log.info('ValueError raised during conversion of parameter %s (%s): %s', parameter.position, parameter.name, e)
            raise ConverterHttp404(value, parameter, 'A parameter could not be converted - see the logs for more detail') from e

        except Exception as e:
            log.info('Exception raised during conversion of parameter %s (%s): %s', parameter.position, parameter.name, e)
            raise ConverterException(value, parameter, 'A parameter could not be converted - see the logs for more detail') from e


Instruction:
Write a Python 3 function for
creating an entry file for the given script map and enapps.

Response:
def create_entry_file(self, filename, script_map, enapps):
        '''Creates an entry file for the given script map'''
        if len(script_map) == 0:
            return

        # create the entry file
        template = MakoTemplate('''
<%! import os %>
// dynamic imports are within functions so they don't happen until called
DMP_CONTEXT.loadBundle({
    %for (app, template), script_paths in script_map.items():

    "${ app }/${ template }": () => [
        %for path in script_paths:
        import(/* webpackMode: "eager" */ "./${ os.path.relpath(path, os.path.dirname(filename)) }"),
        %endfor
    ],
    %endfor

})
''')
        content = template.render(
            enapps=enapps,
            script_map=script_map,
            filename=filename,
        ).strip()

        # ensure the parent directories exist
        if not os.path.exists(os.path.dirname(filename)):
            os.makedirs(os.path.dirname(filename))

        # if the file exists, then consider the options
        file_exists = os.path.exists(filename)
        if file_exists and self.running_inline:
            # running inline means that we're in debug mode and webpack is likely watching, so
            # we don't want to recreate the entry file (and cause webpack to constantly reload)
            # unless we have changes
            with open(filename, 'r') as fin:
                if content == fin.read():
                    return False
        if file_exists and not self.options.get('overwrite'):
            raise CommandError('Refusing to destroy existing file: {} (use --overwrite option or remove the file)'.format(filename))

        # if we get here, write the file
        self.message('Creating {}'.format(os.path.relpath(filename, settings.BASE_DIR)), level=3)
        with open(filename, 'w') as fout:
            fout.write(content)
        return True


Instruction:
Write a Python 3 script for
mapping templates in this app to their scripts. This function deep searches app/templates/* for the templates of this app. Returns the following dictionary with absolute paths: { ( 'appname', 'template1' ): [ '/abs/path/to/scripts/template1.js', '/abs/path/to/scripts/supertemplate1.js' ], ( 'appname', 'template2' ): [ '/abs/path/to/scripts/template2.js', '/abs/path/to/scripts/supertemplate2.js', '/abs/path/to/scripts/supersuper2.js' ], ... } Any files or subdirectories starting with double-underscores (e.g. __dmpcache__) are skipped.

Response:
def generate_script_map(self, config):
        '''
        Maps templates in this app to their scripts.  This function deep searches
        app/templates/* for the templates of this app.  Returns the following
        dictionary with absolute paths:

        {
            ( 'appname', 'template1' ): [ '/abs/path/to/scripts/template1.js', '/abs/path/to/scripts/supertemplate1.js' ],
            ( 'appname', 'template2' ): [ '/abs/path/to/scripts/template2.js', '/abs/path/to/scripts/supertemplate2.js', '/abs/path/to/scripts/supersuper2.js' ],
            ...
        }

        Any files or subdirectories starting with double-underscores (e.g. __dmpcache__) are skipped.
        '''
        script_map = OrderedDict()
        template_root = os.path.join(os.path.relpath(config.path, settings.BASE_DIR), 'templates')
        def recurse(folder):
            subdirs = []
            if os.path.exists(folder):
                for filename in os.listdir(folder):
                    if filename.startswith('__'):
                        continue
                    filerel = os.path.join(folder, filename)
                    if os.path.isdir(filerel):
                        subdirs.append(filerel)

                    elif os.path.isfile(filerel):
                        template_name = os.path.relpath(filerel, template_root)
                        scripts = self.template_scripts(config, template_name)
                        key = ( config.name, os.path.splitext(template_name)[0] )
                        self.message('Found template: {}; static files: {}'.format(key, scripts), level=3)
                        script_map[key] = scripts

            for subdir in subdirs:
                recurse(subdir)

        recurse(template_root)
        return script_map


Instruction:
Can you generate a brief explanation for the following Python 3 code
def template_scripts(self, config, template_name):
        '''
        Returns a list of scripts used by the given template object AND its ancestors.

        This runs a ProviderRun on the given template (as if it were being displayed).
        This allows the WEBPACK_PROVIDERS to provide the JS files to us.
        '''
        dmp = apps.get_app_config('django_mako_plus')
        template_obj = dmp.engine.get_template_loader(config, create=True).get_mako_template(template_name, force=True)
        mako_context = create_mako_context(template_obj)
        inner_run = WebpackProviderRun(mako_context['self'])
        inner_run.run()
        scripts = []
        for tpl in inner_run.templates:
            for p in tpl.providers:
                if os.path.exists(p.absfilepath):
                    scripts.append(p.absfilepath)
        return scripts

Response: Returns a list of scripts used by the given template object AND its ancestors.


Instruction:
Make a summary of the following Python 3 code
def get_response(self, request, *args, **kwargs):
        '''Returns the redirect response for this exception.'''
        # normal process
        response = HttpResponseRedirect(self.redirect_to)
        response[REDIRECT_HEADER_KEY] = self.redirect_to
        return response

Response: Returns the redirect response for this exception.


Instruction:
How would you implement a function in Python 3 that
returns the redirect response for this exception.

Response:
def get_response(self, request):
        '''Returns the redirect response for this exception.'''
        # the redirect key is already placed in the response by HttpResponseJavascriptRedirect
        return HttpResponseJavascriptRedirect(self.redirect_to, *self.args, **self.kwargs)


Instruction:
Can you implement a function in Python 3 that
returns a template loader instance for the given app.

Response:
def get_template_loader(app, subdir='templates'):
    '''
    Convenience method that calls get_template_loader() on the DMP
    template engine instance.
    '''
    dmp = apps.get_app_config('django_mako_plus')
    return dmp.engine.get_template_loader(app, subdir, create=True)


Instruction:
Implement a function in Python 3 to
return a template loader for the given path.

Response:
def get_template_loader_for_path(path, use_cache=True):
    '''
    Convenience method that calls get_template_loader_for_path() on the DMP
    template engine instance.
    '''
    dmp = apps.get_app_config('django_mako_plus')
    return dmp.engine.get_template_loader_for_path(path, use_cache)


Instruction:
Can you generate a brief explanation for the following Python 3 code
def qualified_name(obj):
    '''Returns the fully-qualified name of the given object'''
    if not hasattr(obj, '__module__'):
        obj = obj.__class__
    module = obj.__module__
    if module is None or module == str.__class__.__module__:
        return obj.__qualname__
    return '{}.{}'.format(module, obj.__qualname__)

Response: Returns the fully - qualified name of the given object


Instruction:
Write a Python 3 function that can
import a fully - qualified name from a module.

Response:
def import_qualified(name):
    '''
    Imports a fully-qualified name from a module:

        cls = import_qualified('homepage.views.index.MyForm')

    Raises an ImportError if it can't be ipmorted.
    '''
    parts = name.rsplit('.', 1)
    if len(parts) != 2:
        raise ImportError('Invalid fully-qualified name: {}'.format(name))
    try:
        return getattr(import_module(parts[0]), parts[1])
    except AttributeError:
        raise ImportError('{} not found in module {}'.format(parts[1], parts[0]))


Instruction:
Implement a Python 3 function for
returning the HTML for the given provider group or all groups.

Response:
def links(tself, group=None):
    '''Returns the HTML for the given provider group (or all groups if None)'''
    pr = ProviderRun(tself, group)
    pr.run()
    return mark_safe(pr.getvalue())


Instruction:
Create a Python 3 function to
return the HTML for the given provider group using an app and template name.

Response:
def template_links(request, app, template_name, context=None, group=None, force=True):
    '''
    Returns the HTML for the given provider group, using an app and template name.
    This method should not normally be used (use links() instead).  The use of
    this method is when provider need to be called from regular python code instead
    of from within a rendering template environment.
    '''
    if isinstance(app, str):
        app = apps.get_app_config(app)
    if context is None:
        context = {}
    dmp = apps.get_app_config('django_mako_plus')
    template_obj = dmp.engine.get_template_loader(app, create=True).get_mako_template(template_name, force=force)
    return template_obj_links(request, template_obj, context, group)


Instruction:
Can you tell what is the following Python 3 function doing
def template_obj_links(request, template_obj, context=None, group=None):
    '''
    Returns the HTML for the given provider group, using a template object.
    This method should not normally be used (use links() instead).  The use of
    this method is when provider need to be called from regular python code instead
    of from within a rendering template environment.
    '''
    # the template_obj can be a MakoTemplateAdapter or a Mako Template
    # if our DMP-defined MakoTemplateAdapter, switch to the embedded Mako Template
    template_obj = getattr(template_obj, 'mako_template', template_obj)
    # create a mako context so it seems like we are inside a render
    context_dict = {
        'request': request,
    }
    if isinstance(context, Context):
        for d in context:
            context_dict.update(d)
    elif context is not None:
        context_dict.update(context)
    mako_context = create_mako_context(template_obj, **context_dict)
    return links(mako_context['self'], group=group)

Response: Returns the HTML for the given provider group using a template object.


Instruction:
How would you implement a function in Python 3 that
calls when link is not defined in the settings

Response:
def build_default_link(self):
        '''Called when 'link' is not defined in the settings'''
        attrs = {}
        attrs["rel"] = "stylesheet"
        attrs["href"] ="{}?{:x}".format(
            os.path.join(settings.STATIC_URL, self.filepath).replace(os.path.sep, '/'),
            self.version_id,
        )
        attrs.update(self.options['link_attrs'])
        attrs["data-context"] = self.provider_run.uid       # can't be overridden
        return '<link{} />'.format(flatatt(attrs))


Instruction:
How would you explain what the following Python 3 function does
def build_default_filepath(self):
        '''Called when 'filepath' is not defined in the settings'''
        return os.path.join(
            self.app_config.name,
            'scripts',
            self.template_relpath + '.js',
        )

Response: Called when filepath is not defined in the settings


Instruction:
Explain what the following Python 3 code does
def django_include(context, template_name, **kwargs):
    '''
    Mako tag to include a Django template withing the current DMP (Mako) template.
    Since this is a Django template, it is search for using the Django search
    algorithm (instead of the DMP app-based concept).
    See https://docs.djangoproject.com/en/2.1/topics/templates/.

    The current context is sent to the included template, which makes all context
    variables available to the Django template. Any additional kwargs are added
    to the context.
    '''
    try:
        djengine = engines['django']
    except KeyError as e:
        raise TemplateDoesNotExist("Django template engine not configured in settings, so template cannot be found: {}".format(template_name)) from e
    djtemplate = djengine.get_template(template_name)
    djcontext = {}
    djcontext.update(context)
    djcontext.update(kwargs)
    return djtemplate.render(djcontext, context['request'])

Response: Include a Django template with the current context.


Instruction:
Can you write a function in Python 3 where it
returns a relative path but only if it doesn t start with a pretty parent directory ".."

Response:
def pretty_relpath(path, start):
    '''
    Returns a relative path, but only if it doesn't start with a non-pretty parent directory ".."
    '''
    relpath = os.path.relpath(path, start)
    if relpath.startswith('..'):
        return path
    return relpath


Instruction:
Can you generate a brief explanation for the following Python 3 code
def is_decorated(cls, f):
        '''Returns True if the given function is decorated with @view_function'''
        real_func = inspect.unwrap(f)
        return real_func in cls.DECORATED_FUNCTIONS

Response: Returns True if the given function is decorated with @view_function


Instruction:
Here you have a function in Python 3, explain what it does
def initialize_providers(cls):
        '''Initializes the providers (called from dmp app ready())'''
        dmp = apps.get_app_config('django_mako_plus')
        # regular content providers
        cls.CONTENT_PROVIDERS = []
        for provider_settings in dmp.options[cls.SETTINGS_KEY]:
            # import the class for this provider
            assert 'provider' in provider_settings, "Invalid entry in settings.py: CONTENT_PROVIDERS item must have 'provider' key"
            provider_cls = import_string(provider_settings['provider'])
            # combine options from all of its bases, then from settings.py
            options = {}
            for base in reversed(inspect.getmro(provider_cls)):
                options.update(getattr(base, 'DEFAULT_OPTIONS', {}))
            options.update(provider_settings)
            # add to the list
            if options['enabled']:
                pe = ProviderEntry(provider_cls, options)
                pe.options['template_cache_key'] = '_dmp_provider_{}_'.format(id(pe))
                cls.CONTENT_PROVIDERS.append(pe)

Response: Initializes the providers ( called from dmp app ready


Instruction:
Can you implement a function in Python 3 that
performs the run through the templates and their providers and passes the results to the user.

Response:
def run(self):
        '''Performs the run through the templates and their providers'''
        for tpl in self.templates:
            for provider in tpl.providers:
                provider.provide()


Instruction:
Make a summary of the following Python 3 code
def write(self, content):
        '''Provider instances use this to write to the buffer'''
        self.buffer.write(content)
        if settings.DEBUG:
            self.buffer.write('\n')

Response: Write the content to the buffer.


Instruction:
Can you write a function in Python 3 where it
prepares the sort key for the current locale.

Response:
def prepare_sort_key(self):
        '''
        Triggered by view_function._sort_converters when our sort key should be created.
        This can't be called in the constructor because Django models might not be ready yet.
        '''
        if isinstance(self.convert_type, str):
            try:
                app_name, model_name = self.convert_type.split('.')
            except ValueError:
                raise ImproperlyConfigured('"{}" is not a valid converter type. String-based converter types must be specified in "app.Model" format.'.format(self.convert_type))
            try:
                self.convert_type = apps.get_model(app_name, model_name)
            except LookupError as e:
                raise ImproperlyConfigured('"{}" is not a valid model name. {}'.format(self.convert_type, e))

        # we reverse sort by ( len(mro), source code order ) so subclasses match first
        # on same types, last declared method sorts first
        self.sort_key = ( -1 * len(inspect.getmro(self.convert_type)), -1 * self.source_order )


Instruction:
Create a Python 3 function for
returning the command to run as a list ( see subprocess module )

Response:
def build_command(self):
        '''Returns the command to run, as a list (see subprocess module)'''
        # if defined in settings, run the function or return the string
        if self.options['command']:
            return self.options['command'](self) if callable(self.options['command']) else self.options['command']
        # build the default
        return self.build_default_command()


Instruction:
Can you generate the documentation for the following Python 3 function
def needs_compile(self):
        '''Returns True if self.sourcepath is newer than self.targetpath'''
        try:
            source_mtime = os.stat(self.sourcepath).st_mtime
        except OSError:  # no source for this template, so just return
            return False
        try:
            target_mtime = os.stat(self.targetpath).st_mtime
        except OSError: # target doesn't exist, so compile
            return True
        # both source and target exist, so compile if source newer
        return source_mtime > target_mtime

Response: Returns True if self. sourcepath is newer than self. targetpath


Instruction:
Can you generate a brief explanation for the following Python 3 code
def template_inheritance(obj):
    '''
    Generator that iterates the template and its ancestors.
    The order is from most specialized (furthest descendant) to
    most general (furthest ancestor).

    obj can be either:
        1. Mako Template object
        2. Mako `self` object (available within a rendering template)
    '''
    if isinstance(obj, MakoTemplate):
        obj = create_mako_context(obj)['self']
    elif isinstance(obj, MakoContext):
        obj = obj['self']
    while obj is not None:
        yield obj.template
        obj = obj.inherits

Response: Generator that iterates the template and its ancestors.


Instruction:
How would you explain what the following Python 3 function does
def get_template_debug(template_name, error):
    '''
    This structure is what Django wants when errors occur in templates.
    It gives the user a nice stack trace in the error page during debug.
    '''
    # This is taken from mako.exceptions.html_error_template(), which has an issue
    # in Py3 where files get loaded as bytes but `lines = src.split('\n')` below
    # splits with a string. Not sure if this is a bug or if I'm missing something,
    # but doing a custom debugging template allows a workaround as well as a custom
    # DMP look.
    # I used to have a file in the templates directory for this, but too many users
    # reported TemplateNotFound errors. This function is a bit of a hack, but it only
    # happens during development (and mako.exceptions does this same thing).
    #   /justification
    stacktrace_template = MakoTemplate(r"""
<%! from mako.exceptions import syntax_highlight, pygments_html_formatter %>

<%

    src = tback.source
    line = tback.lineno
    if isinstance(src, bytes):
        src = src.decode()
    if src:
        lines = src.split('\n')
    else:
        lines = None
%>

${tback.errorname}: ${tback.message}

% if lines:

    % for index in range(max(0, line-4),min(len(lines), line+5)):
        <%
        if pygments_html_formatter:
            pygments_html_formatter.linenostart = index + 1
        %>
        % if index + 1 == line:
        <%
        if pygments_html_formatter:
            old_cssclass = pygments_html_formatter.cssclass
            pygments_html_formatter.cssclass = 'error ' + old_cssclass
        %>
            ${lines[index] | n,syntax_highlight(language='mako')}
        <%
        if pygments_html_formatter:
            pygments_html_formatter.cssclass = old_cssclass
        %>
        % else:
            ${lines[index] | n,syntax_highlight(language='mako')}
        % endif
    % endfor

% endif

% for (filename, lineno, function, line) in tback.reverse_traceback:

${filename}, line ${lineno}:

    <%
       if pygments_html_formatter:
           pygments_html_formatter.linenostart = lineno
    %>

${line | n,syntax_highlight(filename)}

% endfor

""")
    tback = RichTraceback(error, error.__traceback__)
    lines = stacktrace_template.render_unicode(tback=tback)
    return {
        'message': '',
        'source_lines': [
            ( '', mark_safe(lines) ),
        ],
        'before': '',
        'during': '',
        'after': '',
        'top': 0,
        'bottom': 0,
        'total': 0,
        'line': tback.lineno or 0,
        'name': template_name,
        'start': 0,
        'end': 0,
    }

Response: Returns a MakoTemplate object that can be used to debug the error page.


Instruction:
Can you write a function in Python 3 where it
returns the name of this template if created from a file or string if not

Response:
def name(self):
        '''Returns the name of this template (if created from a file) or "string" if not'''
        if self.mako_template.filename:
            return os.path.basename(self.mako_template.filename)
        return 'string'


Instruction:
How would you code a function in Python 3 to
render a Mako template using the Mako system.

Response:
def render(self, context=None, request=None, def_name=None):
        '''
        Renders a template using the Mako system.  This method signature conforms to
        the Django template API, which specifies that template.render() returns a string.

            @context  A dictionary of name=value variables to send to the template page.  This can be a real dictionary
                      or a Django Context object.
            @request  The request context from Django.  If this is None, any TEMPLATE_CONTEXT_PROCESSORS defined in your settings
                      file will be ignored but the template will otherwise render fine.
            @def_name Limits output to a specific top-level Mako <%block> or <%def> section within the template.
                      If the section is a <%def>, any parameters must be in the context dictionary.  For example,
                      def_name="foo" will call <%block name="foo"></%block> or <%def name="foo()"></def> within
                      the template.

        Returns the rendered template as a unicode string.

        The method triggers two signals:
            1. dmp_signal_pre_render_template: you can (optionally) return a new Mako Template object from a receiver to replace
               the normal template object that is used for the render operation.
            2. dmp_signal_post_render_template: you can (optionally) return a string to replace the string from the normal
               template object render.
        '''
        dmp = apps.get_app_config('django_mako_plus')
        # set up the context dictionary, which is the variables available throughout the template
        context_dict = {}
        # if request is None, add some default items because the context processors won't happen
        if request is None:
            context_dict['settings'] = settings
            context_dict['STATIC_URL'] = settings.STATIC_URL
        # let the context_processors add variables to the context.
        if not isinstance(context, Context):
            context = Context(context) if request is None else RequestContext(request, context)
        with context.bind_template(self):
            for d in context:
                context_dict.update(d)
        context_dict.pop('self', None)  # some contexts have self in them, and it messes up render_unicode below because we get two selfs

        # send the pre-render signal
        if dmp.options['SIGNALS'] and request is not None:
            for receiver, ret_template_obj in dmp_signal_pre_render_template.send(sender=self, request=request, context=context, template=self.mako_template):
                if ret_template_obj is not None:
                    if isinstance(ret_template_obj, MakoTemplateAdapter):
                        self.mako_template = ret_template_obj.mako_template   # if the signal function sends a MakoTemplateAdapter back, use the real mako template inside of it
                    else:
                        self.mako_template = ret_template_obj                 # if something else, we assume it is a mako.template.Template, so use it as the template

        # do we need to limit down to a specific def?
        # this only finds within the exact template (won't go up the inheritance tree)
        render_obj = self.mako_template
        if def_name is None:
            def_name = self.def_name
        if def_name:  # do we need to limit to just a def?
            render_obj = self.mako_template.get_def(def_name)

        # PRIMARY FUNCTION: render the template
        if log.isEnabledFor(logging.INFO):
            log.info('rendering template %s%s%s', self.name, ('::' if def_name else ''), def_name or '')
        if settings.DEBUG:
            try:
                content = render_obj.render_unicode(**context_dict)
            except Exception as e:
                log.exception('exception raised during template rendering: %s', e)  # to the console
                e.template_debug = get_template_debug('%s%s%s' % (self.name, ('::' if def_name else ''), def_name or ''), e)
                raise
        else:  # this is outside the above "try" loop because in non-DEBUG mode, we want to let the exception throw out of here (without having to re-raise it)
            content = render_obj.render_unicode(**context_dict)

        # send the post-render signal
        if dmp.options['SIGNALS'] and request is not None:
            for receiver, ret_content in dmp_signal_post_render_template.send(sender=self, request=request, context=context, template=self.mako_template, content=content):
                if ret_content is not None:
                    content = ret_content  # sets it to the last non-None return in the signal receiver chain

        # return
        return mark_safe(content)


Instruction:
Create a Python 3 function for
rendering the template and returns an HttpResponse object containing the rendered content.

Response:
def render_to_response(self, context=None, request=None, def_name=None, content_type=None, status=None, charset=None):
        '''
        Renders the template and returns an HttpRequest object containing its content.

        This method returns a django.http.Http404 exception if the template is not found.
        If the template raises a django_mako_plus.RedirectException, the browser is redirected to
        the given page, and a new request from the browser restarts the entire DMP routing process.
        If the template raises a django_mako_plus.InternalRedirectException, the entire DMP
        routing process is restarted internally (the browser doesn't see the redirect).

            @request      The request context from Django.  If this is None, any TEMPLATE_CONTEXT_PROCESSORS defined in your settings
                          file will be ignored but the template will otherwise render fine.
            @template     The template file path to render.  This is relative to the app_path/controller_TEMPLATES_DIR/ directory.
                          For example, to render app_path/templates/page1, set template="page1.html", assuming you have
                          set up the variables as described in the documentation above.
            @context      A dictionary of name=value variables to send to the template page.  This can be a real dictionary
                          or a Django Context object.
            @def_name     Limits output to a specific top-level Mako <%block> or <%def> section within the template.
                          For example, def_name="foo" will call <%block name="foo"></%block> or <%def name="foo()"></def> within the template.
            @content_type The MIME type of the response.  Defaults to settings.DEFAULT_CONTENT_TYPE (usually 'text/html').
            @status       The HTTP response status code.  Defaults to 200 (OK).
            @charset      The charset to encode the processed template string (the output) with.  Defaults to settings.DEFAULT_CHARSET (usually 'utf-8').

        The method triggers two signals:
            1. dmp_signal_pre_render_template: you can (optionally) return a new Mako Template object from a receiver to replace
               the normal template object that is used for the render operation.
            2. dmp_signal_post_render_template: you can (optionally) return a string to replace the string from the normal
               template object render.
        '''
        try:
            if content_type is None:
                content_type = mimetypes.types_map.get(os.path.splitext(self.mako_template.filename)[1].lower(), settings.DEFAULT_CONTENT_TYPE)
            if charset is None:
                charset = settings.DEFAULT_CHARSET
            if status is None:
                status = 200
            content = self.render(context=context, request=request, def_name=def_name)
            return HttpResponse(content.encode(charset), content_type='%s; charset=%s' % (content_type, charset), status=status)

        except RedirectException: # redirect to another page
            e = sys.exc_info()[1]
            if request is None:
                log.info('a template redirected processing to %s', e.redirect_to)
            else:
                log.info('view function %s.%s redirected processing to %s', request.dmp.module, request.dmp.function, e.redirect_to)
            # send the signal
            dmp = apps.get_app_config('django_mako_plus')
            if dmp.options['SIGNALS']:
                dmp_signal_redirect_exception.send(sender=sys.modules[__name__], request=request, exc=e)
            # send the browser the redirect command
            return e.get_response(request)


Instruction:
Can you create a Python 3 function that
retrieves the given parser action object by its dest attribute

Response:
def get_action_by_dest(self, parser, dest):
        '''Retrieves the given parser action object by its dest= attribute'''
        for action in parser._actions:
            if action.dest == dest:
                return action
        return None


Instruction:
Implement a Python 3 function for
placing this in execute because then subclass handle doesn t have to call super

Response:
def execute(self, *args, **options):
        '''Placing this in execute because then subclass handle() don't have to call super'''
        if options['verbose']:
            options['verbosity'] = 3
        if options['quiet']:
            options['verbosity'] = 0
        self.verbosity = options.get('verbosity', 1)
        super().execute(*args, **options)


Instruction:
How would you explain what the following Python 3 function does
def message(self, msg='', level=1, tab=0):
        '''Print a message to the console'''
        if self.verbosity >= level:
            self.stdout.write('{}{}'.format('    ' * tab, msg))

Response: Print a message to the console


Instruction:
Explain what the following Python 3 code does
def b58enc(uid):
    '''Encodes a UID to an 11-length string, encoded using base58 url-safe alphabet'''
    # note: i tested a buffer array too, but string concat was 2x faster
    if not isinstance(uid, int):
        raise ValueError('Invalid integer: {}'.format(uid))
    if uid == 0:
        return BASE58CHARS[0]
    enc_uid = ""
    while uid:
        uid, r = divmod(uid, 58)
        enc_uid = BASE58CHARS[r] + enc_uid
    return enc_uid

Response: Encodes a UID to an 11 - length string encoded using base58 url - safe alphabet


Instruction:
Write a Python 3 script for
decoding a UID from base58 url - safe alphabet back to int.

Response:
def b58dec(enc_uid):
    '''Decodes a UID from base58, url-safe alphabet back to int.'''
    if isinstance(enc_uid, str):
        pass
    elif isinstance(enc_uid, bytes):
        enc_uid = enc_uid.decode('utf8')
    else:
        raise ValueError('Cannot decode this type: {}'.format(enc_uid))
    uid = 0
    try:
        for i, ch in enumerate(enc_uid):
            uid = (uid * 58) + BASE58INDEX[ch]
    except KeyError:
        raise ValueError('Invalid character: "{}" ("{}", index 5)'.format(ch, enc_uid, i))
    return uid


Instruction:
Can you tell what is the following Python 3 function doing
def minify(text, minifier):
    '''Minifies the source text (if needed)'''
    # there really isn't a good way to know if a file is already minified.
    # our heuristic is if source is more than 50 bytes greater of dest OR
    # if a hard return is found in the first 50 chars, we assume it is not minified.
    minified = minifier(text)
    if  abs(len(text) - len(minified)) > 50 or '\n' in text[:50]:
        return minified
    return text

Response: Minifies the source text ( if needed )


Instruction:
Can you generate a brief explanation for the following Python 3 code
def match(self, fname, flevel, ftype):
        '''Returns the result score if the file matches this rule'''
        # if filetype is the same
        # and level isn't set or level is the same
        # and pattern matche the filename
        if self.filetype == ftype and (self.level is None or self.level == flevel) and fnmatch.fnmatch(fname, self.pattern):
            return self.score
        return 0

Response: Returns the result score if the file matches this rule


Instruction:
Given the following Python 3 function, write the documentation
def create_rules(self):
        '''Adds rules for the command line options'''
        dmp = apps.get_app_config('django_mako_plus')
        # the default
        rules = [
            # files are included by default
            Rule('*',                                    level=None, filetype=TYPE_FILE,      score=1),
            # files at the app level are skipped
            Rule('*',                                    level=0,    filetype=TYPE_FILE,      score=-2),
            # directories are recursed by default
            Rule('*',                                    level=None, filetype=TYPE_DIRECTORY, score=1),
            # directories at the app level are skipped
            Rule('*',                                    level=0,    filetype=TYPE_DIRECTORY, score=-2),

            # media, scripts, styles directories are what we want to copy
            Rule('media',                                level=0,    filetype=TYPE_DIRECTORY, score=6),
            Rule('scripts',                              level=0,    filetype=TYPE_DIRECTORY, score=6),
            Rule('styles',                               level=0,    filetype=TYPE_DIRECTORY, score=6),

            # ignore the template cache directories
            Rule(dmp.options['TEMPLATES_CACHE_DIR'],     level=None, filetype=TYPE_DIRECTORY, score=-3),
            # ignore python cache directories
            Rule('__pycache__',                          level=None, filetype=TYPE_DIRECTORY, score=-3),
            # ignore compiled python files
            Rule('*.pyc',                                level=None, filetype=TYPE_FILE,      score=-3),
        ]
        # include rules have score of 50 because they trump all initial rules
        for pattern in (self.options.get('include_dir') or []):
            self.message('Setting rule - recurse directories: {}'.format(pattern), 1)
            rules.append(Rule(pattern, level=None, filetype=TYPE_DIRECTORY, score=50))
        for pattern in (self.options.get('include_file') or []):
            self.message('Setting rule - include files: {}'.format(pattern), 1)
            rules.append(Rule(pattern, level=None, filetype=TYPE_FILE, score=50))
        # skip rules have score of 100 because they trump everything, including the includes from the command line
        for pattern in (self.options.get('skip_dir') or []):
            self.message('Setting rule - skip directories: {}'.format(pattern), 1)
            rules.append(Rule(pattern, level=None, filetype=TYPE_DIRECTORY, score=-100))
        for pattern in (self.options.get('skip_file') or []):
            self.message('Setting rule - skip files: {}'.format(pattern), 1)
            rules.append(Rule(pattern, level=None, filetype=TYPE_FILE, score=-100))
        return rules

Response: Adds rules for the command line options


Instruction:
Write a Python 3 function that can
copy the static files from one directory to another.

Response:
def copy_dir(self, source, dest, level=0):
        '''Copies the static files from one directory to another.  If this command is run, we assume the user wants to overwrite any existing files.'''
        encoding = settings.DEFAULT_CHARSET or 'utf8'
        msglevel = 2 if level == 0 else 3
        self.message('Directory: {}'.format(source), msglevel, level)

        # create a directory for this app
        if not os.path.exists(dest):
            self.message('Creating directory: {}'.format(dest), msglevel, level+1)
            os.mkdir(dest)

        # go through the files in this app
        for fname in os.listdir(source):
            source_path = os.path.join(source, fname)
            dest_path = os.path.join(dest, fname)
            ext = os.path.splitext(fname)[1].lower()

            # get the score for this file
            score = 0
            for rule in self.rules:
                score += rule.match(fname, level, TYPE_DIRECTORY if os.path.isdir(source_path) else TYPE_FILE)

            # if score is not above zero, we skip this file
            if score <= 0:
                self.message('Skipping file with score {}: {}'.format(score, source_path), msglevel, level+1)
                continue

            ### if we get here, we need to copy the file ###

            # if a directory, recurse to it
            if os.path.isdir(source_path):
                self.message('Creating directory with score {}: {}'.format(score, source_path), msglevel, level+1)
                # create it in the destination and recurse
                if not os.path.exists(dest_path):
                    os.mkdir(dest_path)
                elif not os.path.isdir(dest_path):  # could be a file or link
                    os.unlink(dest_path)
                    os.mkdir(dest_path)
                self.copy_dir(source_path, dest_path, level+1)

            # if a regular Javscript file, run through the static file processors (scripts group)
            elif ext == '.js' and not self.options.get('no_minify') and jsmin:
                self.message('Including and minifying file with score {}: {}'.format(score, source_path), msglevel, level+1)
                with open(source_path, encoding=encoding) as fin:
                    with open(dest_path, 'w', encoding=encoding) as fout:
                        minified = minify(fin.read(), jsmin)
                        fout.write(minified)

            # if a CSS file, run through the static file processors (styles group)
            elif ext == '.css' and not self.options.get('no_minify') and cssmin:
                self.message('Including and minifying file with score {}: {}'.format(score, source_path), msglevel, level+1)
                with open(source_path, encoding=encoding) as fin:
                    with open(dest_path, 'w', encoding=encoding) as fout:
                        minified = minify(fin.read(), cssmin)
                        fout.write(minified)

            # otherwise, just copy the file
            else:
                self.message('Including file with score {}: {}'.format(score, source_path), msglevel, level+1)
                shutil.copy2(source_path, dest_path)


Instruction:
Given the following Python 3 function, write the documentation
def dmp_include(context, template_name, def_name=None, **kwargs):
    '''
    Includes a DMP (Mako) template into a normal django template.

    context:        automatically provided
    template_name:  specified as "app/template"
    def_name:       optional block to render within the template

    Example:
        {% load django_mako_plus %}
        {% dmp_include "homepage/bsnav_dj.html" %}
        or
        {% dmp_include "homepage/bsnav_dj.html" "blockname" %}
    '''
    dmp = apps.get_app_config('django_mako_plus')
    template = dmp.engine.get_template(template_name)
    dmpcontext = context.flatten()
    dmpcontext.update(kwargs)
    return mark_safe(template.render(
        context=dmpcontext,
        request=context.get('request'),
        def_name=def_name
    ))

Response: Include a DMP template into a normal django template.


Instruction:
Can you generate a brief explanation for the following Python 3 code
def render(self, template, context=None, def_name=None, subdir='templates', content_type=None, status=None, charset=None):
        '''App-specific render function that renders templates in the *current app*, attached to the request for convenience'''
        template_adapter = self.get_template_loader(subdir).get_template(template)
        return getattr(template_adapter, 'render_to_response')(context=context, request=self.request, def_name=def_name, content_type=content_type, status=status, charset=charset)

Response: App - specific render function that renders templates in the current app attached to the request for convenience


Instruction:
Can you generate a brief explanation for the following Python 3 code
def render_to_string(self, template, context=None, def_name=None, subdir='templates'):
        '''App-specific render function that renders templates in the *current app*, attached to the request for convenience'''
        template_adapter = self.get_template_loader(subdir).get_template(template)
        return getattr(template_adapter, 'render')(context=context, request=self.request, def_name=def_name)

Response: App - specific render function that renders templates in the current app attached to the request for convenience


Instruction:
Write a Python 3 function that can
call by Django when the app is ready for use.

Response:
def ready(self):
        '''Called by Django when the app is ready for use.'''
        # set up the options
        self.options = {}
        self.options.update(DEFAULT_OPTIONS)
        for template_engine in settings.TEMPLATES:
            if template_engine.get('BACKEND', '').startswith('django_mako_plus'):
                self.options.update(template_engine.get('OPTIONS', {}))

        # dmp-enabled apps registry
        self.registration_lock = threading.RLock()
        self.registered_apps = {}

        # init the template engine
        self.engine = engines['django_mako_plus']

        # default imports on every compiled template
        self.template_imports = [
            'import django_mako_plus',
            'import django.utils.html',     # used in template.py
        ]
        self.template_imports.extend(self.options['DEFAULT_TEMPLATE_IMPORTS'])

        # initialize the list of providers
        ProviderRun.initialize_providers()

        # set up the parameter converters (can't import until apps are set up)
        from .converter.base import ParameterConverter
        ParameterConverter._sort_converters(app_ready=True)


Instruction:
Given the following Python 3 function, write the documentation
def register_app(self, app=None):
        '''
        Registers an app as a "DMP-enabled" app.  Normally, DMP does this
        automatically when included in urls.py.

        If app is None, the DEFAULT_APP is registered.
        '''
        app = app or self.options['DEFAULT_APP']
        if not app:
            raise ImproperlyConfigured('An app name is required because DEFAULT_APP is empty - please use a '
                                        'valid app name or set the DEFAULT_APP in settings')
        if isinstance(app, str):
            app = apps.get_app_config(app)

        # since this only runs at startup, this lock doesn't affect performance
        with self.registration_lock:
            # short circuit if already registered
            if app.name in self.registered_apps:
                return

            # first time for this app, so add to our dictionary
            self.registered_apps[app.name] = app

            # set up the template, script, and style renderers
            # these create and cache just by accessing them
            self.engine.get_template_loader(app, 'templates', create=True)
            self.engine.get_template_loader(app, 'scripts', create=True)
            self.engine.get_template_loader(app, 'styles', create=True)

            # send the registration signal
            if self.options['SIGNALS']:
                dmp_signal_register_app.send(sender=self, app_config=app)

Response: Registers an app as a DMP - enabled app.


Instruction:
Implement a function in Python 3 to
return true if the given app is registered with DMP

Response:
def is_registered_app(self, app):
        '''Returns true if the given app/app name is registered with DMP'''
        if app is None:
            return False
        if isinstance(app, AppConfig):
            app = app.name
        return app in self.registered_apps


Instruction:
Make a summary of the following Python 3 code
def get(self, idx, default=''):
        '''Returns the element at idx, or default if idx is beyond the length of the list'''
        # if the index is beyond the length of the list, return ''
        if isinstance(idx, int) and (idx >= len(self) or idx < -1 * len(self)):
            return default
        # else do the regular list function (for int, slice types, etc.)
        return super().__getitem__(idx)

Response: Returns the element at idx or default if idx is beyond the length of the list.


Instruction:
Create a Python 3 function for
converting value to int or float

Response:
def convert_int(value, parameter):
    '''
    Converts to int or float:
        '', '-', None convert to parameter default
        Anything else uses int() or float() constructor
    '''
    value = _check_default(value, parameter, ( '', '-', None ))
    if value is None or isinstance(value, int):
        return value
    try:
        return int(value)
    except Exception as e:
        raise ValueError(str(e))


Instruction:
Can you generate a brief explanation for the following Python 3 code
def convert_float(value, parameter):
    '''
    Converts to int or float:
        '', '-', None convert to parameter default
        Anything else uses int() or float() constructor
    '''
    value = _check_default(value, parameter, ( '', '-', None ))
    if value is None or isinstance(value, float):
        return value
    try:
        return float(value)
    except Exception as e:
        raise ValueError(str(e))

Response: Converts value to float or returns default value


Instruction:
Can you write a function in Python 3 where it
converts value to decimal. Decimal

Response:
def convert_decimal(value, parameter):
    '''
    Converts to decimal.Decimal:
        '', '-', None convert to parameter default
        Anything else uses Decimal constructor
    '''
    value = _check_default(value, parameter, ( '', '-', None ))
    if value is None or isinstance(value, decimal.Decimal):
        return value
    try:
        return decimal.Decimal(value)
    except Exception as e:
        raise ValueError(str(e))


Instruction:
Implement a Python 3 function for
converting a string to boolean.

Response:
def convert_boolean(value, parameter, default=False):
    '''
    Converts to boolean (only the first char of the value is used):
        '', '-', None convert to parameter default
        'f', 'F', '0', False always convert to False
        Anything else converts to True.
    '''
    value = _check_default(value, parameter, ( '', '-', None ))
    if isinstance(value, bool):
        return value
    if isinstance(value, str) and len(value) > 0:
        value = value[0]
    return value not in ( 'f', 'F', '0', False, None )