#!/usr/bin/python
# -*- coding: UTF-8 -*-
 
class FooParent(object):
  def __init__(self):
    self.parent = 'I\'m the parent.'
    print ('Parent')
  
  def bar(self,message):
    print ("%s from Parent" % message)
 
class FooChild(FooParent):
  def __init__(self):
    # super(FooChild,self) 首先找到 FooChild 的父类（就是类 FooParent），然后把类B的对象 FooChild 转换为类 FooParent 的对象
    super(FooChild,self).__init__()  
    print ('Child')
    
  def bar(self,message):
    super(FooChild, self).bar(message)
    print ('Child bar fuction')
    print (self.parent)
 
if __name__ == '__main__':
  fooChild = FooChild()
  fooChild.bar('HelloWorld')

class C:
  def minus(self,x):
    return x/2

class D(C):
  def minus(self,x):
    super(D, self).minus()
    print 'hello'

class A:
  def __init__(self):
    self.n = 10

  def minus(self, m):
    self.n -= m


class B(A):
  def __init__(self):
    self.n = 7

  def minus(self, m):
    super(B,self).minus(m)
    self.n -= 3
B()
B(2)
print b.n