after decorator example

after_decorator.py

def do_the_other_thing(run, output): 
    def wrap(self): 
        run(self) 
        output(self) 
    return wrap 
 
class A: 
    name='a' 
    def run(self): 
        pass 
 
    def hello(self): 
        print('hello') 
 
    def output(self): 
        self.hello() 
 
    def __init_subclass__(cls): 
        super().__init_subclass__() 
        cls.run = do_the_other_thing(cls.run, cls.output)
        # do some other work 
 
class B(A): 
    name='b' 
    def run(self): 
         print("running!")