runtime error

Traceback (most recent call last): File "/home/user/app/app.py", line 14, in <module> iface = gr.Interface(fn=download_file, File "/usr/local/lib/python3.10/site-packages/gradio/interface.py", line 196, in __init__ raise TypeError( TypeError: outputs must be a string, list, or Component, not <function serve_file at 0x7fe2debcd1b0>

Container logs: