When Objects are Alike(Chapter 3 of Python 3 Object Oriented Programming)

 1 class BaseClass:
 2     num_base_calls = 0
 3 
 4     def call_me(self):
 5         print("Calling method on Base Class")
 6         self.num_base_calls += 1
 7 
 8 class LeftSubclass(BaseClass):
 9     num_left_calls = 0
10 
11     def call_me(self):
12         BaseClass.call_me(self)
13         print("Calling method on Left Subclass")
14         self.num_left_calls += 1
15 
16 class RightSubclass(BaseClass):
17     num_right_calls = 0
18 
19     def call_me(self):
20         BaseClass.call_me(self)
21         print("Calling method on Right Subclass")
22         self.num_right_calls += 1
23 
24 class Subclass(LeftSubclass, RightSubclass):
25     num_sub_calls = 0
26 
27     def call_me(self):
28         LeftSubclass.call_me(self)
29         RightSubclass.call_me(self)
30         print("Calling method on Subclass")
31         self.num_sub_calls += 1