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unnecessary-return-none (RET501)

Added in v0.0.154 · Related issues · View source

Derived from the flake8-return linter.

Fix is always available.

What it does

Checks for the presence of a return None statement when None is the only possible return value.

Why is this bad?

Python implicitly assumes return None if an explicit return value is omitted. Therefore, explicitly returning None is redundant and should be avoided when it is the only possible return value across all code paths in a given function.

Example

def foo(bar):
    if not bar:
        return
    return None

Use instead:

def foo(bar):
    if not bar:
        return
    return

Fix safety

This rule's fix is marked as unsafe for cases in which comments would be dropped from the return statement.