class Demo(object): def instance_method(self, your_para): """ this is an instance_method you should call it like the follow: a = Demo() a.instance_method(your_para) plus: in python, we denote 'cls' as latent para of Class while 'self' as latent para of the instance of the Class :param your_para:  :return:  """ print("call instance_method and get:", your_para) @classmethod def class_method(cls, your_para): """ this is a class_method you can call it like the follow: method1: a = Demo() a.class_method(your_para) method2: Demo.class_method plus: in python, we denote 'cls' as latent para of Class while 'self' as latent para of the instance of the Class :param your_para:  :return:  """ print("call class_method and get:", your_para) @staticmethod def static_method(your_para): """ this is a static_method and you can call it like the  methods of class_method :param your_para:  :return:  """ print("call static_method and get:", your_para)

class Fruit(object): total = 0 # 這是一個類屬性 @classmethod def print_total(cls): print('this is the ', cls, '.total:', cls.total, ' and its id: ', id(cls.total)) # cls是類本身，打印類屬性total的值 print('this is the Fruit.total:', Fruit.total, 'and its id: ', id(Fruit.total)) print("=======================") @classmethod def set(cls, value): cls.total = valueclass Apple(Fruit): passclass Orange(Fruit): passapp1 = Apple()app1.set(10)app1.print_total()Apple.print_total()Fruit.set(2)app1.print_total()Fruit.print_total()"""output:this is the <class '__main__.Apple'> .total: 10 and its id: 1355201264this is the Fruit.total: 0 and its id: 1355200944=======================this is the <class '__main__.Apple'> .total: 10 and its id: 1355201264this is the Fruit.total: 0 and its id: 1355200944=======================this is the <class '__main__.Apple'> .total: 10 and its id: 1355201264this is the Fruit.total: 2 and its id: 1355201008=======================this is the <class '__main__.Fruit'> .total: 2 and its id: 1355201008this is the Fruit.total: 2 and its id: 1355201008======================="""