[Python] How to annotate return type for a Python function returning a class defined within...

Suppose I have a decorator defined using a callable class as a wrapper. For example:

from functools import wraps
from typing import Any, Callable, cast

def decorator(*args: Any, **kwargs: Any) -> Any:
class Wrapper:
def __init__(self) -> None:
self.args = args
self.kwargs = kwargs

def __call__(self, func: Callable[..., Any]) -> Callable[..., Any]:
@wraps(func)
def wrapper(*args: Any, **kwargs: Any) -> Any:
return func(*args, **kwargs)

return wrapper

return Wrapper()


How to properly annotate type its return type?

So far, I found that the following inheritance "trick" works as I expect:

from functools import wraps
from typing import Any, Callable, cast

class BaseWrapper:
def __call__(self, func: Callable[..., Any]) -> Callable[..., Any]:
@wraps(func)
def wrapper(*args: Any, **kwargs: Any) -> Any:
return func(*args, **kwargs)

return wrapper


def decorator(*args: Any, **kwargs: Any) -> BaseWrapper:
class Wrapper(BaseWrapper):
def __init__(self) -> None:
self.args = args
self.kwargs = kwargs

return Wrapper()


But is there any other way? I just don't want to have the BaseWrapper in the module's namespace.

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