:x: Problematic code:
def foo(): pass
:heavy_check_mark: Correct code:
def foo(): """A dummy docstring."""
Missing function or method docstring used when a function or method has no docstring. Some special methods like __init__, protected, private functions, setters and deleters do not require a docstring (learn more from testscases). It's a good practice to describe what a function does for other programmers.