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_num
13 self.name = name
14 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__)