#!/usr/bin/python# -*- coding:UTF-8 -*-class Dog():    #construct    #类变量可以不用显式定义在类的头部 但是最好不要这样做    #类变量不显式区分public 和 private, 隐式规则:变量前缀是__，则表示该变量是private变量，否则为public    def __init__(self, name, age):        self.name = name        self.age = age             def sit(self):        print(self.name.title() + " is now sitting")    def roll_over(self):        print(self.name.title() + " rolled over")dog = Dog("dabai", 10) dog.sit()dog.roll_over();print dog.name

#!/usr/bin/python# -*- coding:UTF-8 -*-class Animal():    def __init__(self, animal_type, name):        self.animal_type = animal_type;        self.name = name;class Dog(Animal):    def __init__(self, name, age):        self.name = name        #python2的语法        #python3的语法: super().__init__(param1, param2, ...)        Animal.__init__(self, "reptiles", name)        self.age = age         self.animal_type = "reptiles"        def sit(self):        print(self.name.title() + " is now sitting")    def roll_over(self):        print(self.name.title() + " rolled over")dog = Dog("dabai", 10)dog.sit()dog.roll_over();print dog.nameprint dog.animal_type