python 父类方法中使用不同的子类中的不同类对象

 # coding:utf-8

 class Animal(object):
     def __init__(self):
         self._name = None
         self._f = None

     def eat(self):
         print("%s吃%s" % (self._name, self._f().food()))

 class Dog(Animal):
     def __init__(self):
         Animal.__init__(self)
         self._f = DogFood
         self._name = "狗"

 class DogFood():
     def food(self):
         return "狗粮"

 class Cat(Animal):
     def __init__(self):
         Animal.__init__(self)
         self._name = "猫"
         self._f = CatFood

 class CatFood():
     def food(self):
         return "猫粮"

 dog = Dog()
 dog.eat()
 cat = Cat()
 cat.eat()

狗吃狗粮
猫吃猫粮

 # coding:utf-8

 class CatFood():
     def food(self, food_name):
         self.food_name = food_name

 cf = CatFood

 cf1 = CatFood()
 cf1.food("鱼")
 cf2 = CatFood()
 cf2.food("粥")

 print(cf1.food_name)
 print(cf2.food_name)

鱼
粥

 # coding:utf-8

 class CatFood():
     def food(self, food_name):
         self.food_name = food_name

 cf = CatFood

 cf1 = CatFood()
 cf1.food("鱼")
 cf2 = CatFood()
 cf2.food("粥")

 print(CatFood)
 print(cf)
 print(cf1)

<class '__main__.CatFood'>
<class '__main__.CatFood'>
<__main__.CatFood object at 0x000000000279B320>

cf CatFood 是类对象

cf1是实例对象