method setter.py

from typing import Callable


class B:
    def b(self):
        ...

    @property
    def bb(self) -> Callable:
        return self.b

    @bb.setter
    def bb(self, new: Callable):
        self.b = new


if __name__ == '__main__':
    b = B()
    b.bb = print
    b.b('hello world')