python2和python3的继承

 1 #_*_coding:utf-8_*_
 2 #__author__ = "csy"
 3 
 4 class A:
 5     def __init__(self):
 6         print("A")
 7 
 8 class B(A):
 9     pass
10     #def __init__(self):
11     #    print("B")
12 
13 class C(A):
14     def __init__(self):
15         print("C")
16 
17 class D(B,C):
18     pass
19     #def __init__(self):
20     #    print("D")
21 
22 d1 = D()