How to typehint the return type of decorated functions?

[HMaker]

It seems Pylance is unable to infer the return type of decorated functions, I tried

import typing

ReturnType = typing.TypeVar('ReturnType')
def my_parametrized_decorator(my_parameter):
    def decorator(decorated_func: typing.Callable[..., typing.Awaitable[ReturnType]]):
        async def wrapper(*args, **kwargs):
            return await decorated_func(*args, **kwargs)
        return wrapper
    return decorator

@my_parametrized_decorator('foo')
async def foo() -> typing.List[str]:
    return ['foo', 'bar']

I expected Pylance to show the return type of foo is List[str] but it shows ReturnType

[erictraut]

Please refer to this issue: microsoft/pyright#774

[HMaker]

It worked, thanks.