5-2、类的继承与多态

# 继承中的多态度
# ABCMeta就是让你的类变成一个纯虚类，子类必须实现某个方法，这个方法在父类中用@abc.abstractmethod修饰
from abc import ABCMeta, abstractmethod


class Pet(object, metaclass=ABCMeta):
    def __init__(self, nickname):
        self._nickname = nickname

    @abstractmethod
    def make_voice(self):
        pass


class Dog(Pet):
    def make_voice(self):
        print('%s在汪汪汪' % self._nickname)


class Sheep(Pet):
    def make_voice(self):
        print('%s在咩咩咩' % self._nickname)


def main():
    pets = [Dog('dog'), Sheep('sheep')]
    for i in pets:
        i.make_voice()


if __name__ == '__main__':
    main()