Decorated Function Should Be Considered Used

Functions with a decorator are considered unused, leading to situations like https://github.com/PyCQA/pyflakes/issues/320 and https://github.com/sympy/sympy/issues/17795.

If I run flake8 on the:

def my_overload(func):
    print(func)
    pass

@my_overload
def utf8(value: bytes) -> bytes:
    pass

@my_overload
def utf8(value: str) -> bytes:
    pass

def utf8(value):
    pass  # actual implementation

I get:

test.py:8:1: F811 redefinition of unused 'utf8' from line 4
test.py:12:1: F811 redefinition of unused 'utf8' from line 8

But the semantically-equivalent:

def utf8(value: bytes) -> bytes:
    pass
my_overload(utf8)

def utf8(value: str) -> bytes:
    pass
my_overload(utf8)

def utf8(value):
    pass  # actual implementation

Does not have any errors. As in my example above, annotations to functions have arbitrary side-effects and should be considered a use of the function

Alternatives:
I can either add an additional prepend overload to my own decorator

def my_decorator(func):
    return func

@overload
@my_decorator
def utf8(value: None) -> None:
    pass

Or I can add two noqa per overloaded function declaration:

@my_overload  # noqa
def utf8(value: str) -> bytes:  # noqa
    pass

These both work for now but it would be nice if I didn't have to do them.

The issue names no repository files or tests. Start by reproducing the decorator and equivalent direct-call examples, then trace the existing unused-name and F811 analysis; done means decorated definitions are treated as used without suppressing genuine redefinition warnings.