8.8 多态

# 提高代码的兼容性 让代码的调度更加灵活
class Dog:
    def shout(self):
        print("汪汪汪")
class Cat:
    def shout(self):
        print("喵喵喵")
def shout(obj):
    obj.shout()
cat = Cat()
dog = Dog()
shout(cat)
shout(dog)