定义一个人的类，人有头、躯干、手、脚等数据属性，这几个属性又可以是通过一个类实例化的对象，这就是组合

1 class Hand: 2     pass 3 class Foot: 4     pass 5 class Trunk: 6     pass 7 class Head: 8     pass 9 10 class Person:11     def __init__(self,id_num,name):12         self.id_num = id_num13         self.name = name14         self.hand = Hand()15         self.foot = Foot()16         self.trunk = Trunk()17         self.head = Head()18 #通过上例可以发现，可以将单独的类组合在一起放入到Person这个大类里19 p = Person('6125221111111','Meanwey')20 print(p.__dict__)