Type-aware Python Decorator

type_aware_python_decorator.py

P = ParamSpec("P")
RT = TypeVar("RT")

# By using ParamSpec, you are able to capture the original function's args and kwargs and forward
# them through the decorator in a way that static analyzes like MyPy, and also ide's like PyCharm
# will be happy ;-)

def your_decorator(f: Callable[P, RT]) -> Callable[P, RT]:
    @wraps(f)
    def decorated_function(*args: P.args, **kwargs: P.kwargs) -> RT:
        # Do the stuff you need the decorator for

        # Run the original function
        return f(*args, **kwargs)

    return decorated_function