Type hint for inheritance from parameter

I am trying to get proper auto-completion for a decorated class. The Problem is that the decorator doesn't just change the class but it creates and returns a new one, derived from the decorated class and another class.
In other words, I need to annotate a functions return value as the parameter and a base class.
Here a simplified example:

class A:
    def func_a(self): pass

def decorator(cls): # what type hint comes here?
    class Result(cls, A):
        pass
    return Result

@decorator
class B:
    def func_b(self): pass

obj = B()
obj.func_a()
obj.func_b()

Here my IDE detects func_a but not func_b.

In TypeScript the solution would be something like

decorator<T>(cls: T): A & T

It seems python doesn't have this & operator for type hints. Which annotation do I use? Or is it just not possible?