The python "around advice"

Like java, without modifying the source code, conduct pre- and post-function method to add a strong

 

class Old():
    def do_sth(self):
        print('do something....')

class MiddleWare():
    def __init__(self,old):
        self.old = old

    DEF  __call__ (Self, * args, ** kwargs):
         Print ( ' do something before the Old # do_sth method, the pre-enhancement ' )
        RET = self.old (* args, ** kwargs)
         Print ( ' do something after the Old # do_sth method, the pre-enhancement ' )
         return RET



if __name__ == '__main__':
    old1= Old()
    old1.do_sth()

    Print ( ' --------------- adding a strong function of the method MiddleWare do_sth ------------------- class ' )
    old= Old()
    old.do_sth = MiddleWare(old.do_sth)
    old.do_sth()