Python: force typecasting a class to another

gistfile1.txt

class A:

    def __init__(self, name):
        self.name = name

    def execute(self):
        raise NotImplementedError()


class B:
    def __init__(self, name):
        self.name = name
    
    def execute(self):
        print(self.name)


inst = A("this")
inst.execute()  # NotImplementedError

inst.__class__ = B
inst.execute()  # this