Python __str__函数

class Cat:
        def __init__(self,_name):
                self.name = _name
        def __str__(self):
                return "i am %s"%self.name
        def show(self):
                print("name is %s"%self.name)


tom = Cat("tom")

tom.show()

print(tom)


print("------------");

lanmao = Cat("lanpang")

lanmao.show()

print(lanmao)

__str__函数要求有返回值，必须有return,
__str__函数功能是将对象字符串化