1.基本繼承圖解

1.1實例化一個Contact類的對象c

1.2實例化一個Supplier類的對象s

1.3訪問對象的屬性

1.4訪問對象s的方法

1.5類變數詳解

如果從新定義c.all_contacts = "xxxxxx"；那麼，對象c擁有一個新的屬性all_contacts，其值為"xxxxxx"。這個c對象屬性的修改，不影響Contact.all_contacts, Supplier.all_contacts, s.all_contacts的值。

註：上述通過對象訪問類變數，其實都是訪問同一個值，它們都屬於Contact.all_contacts；只要Contact.all_contacts不修改，實例化的對象就不會修改。

 2上述代碼驗證

In [1]: class mySubclass(object):  #繼承的基本語法
   ...:     pass
   ...:

In [2]: class Contact:                  #父類定義
   ...:     all_contacts = []
   ...:     def __init__(self, name, email):
   ...:         self.name = name
   ...:         self.email = email
   ...:         Contact.all_contacts.append(self)
   ...:

In [3]: class Supplier(Contact):    #子類定義，繼承了Contact類
   ...:     def order(self, order):
   ...:         print("If this were a real system we would send "
   ...:         "{} order to {} ".format(order, self.name))
   ...:

In [4]: c = Contact("Some Body", "[email protected]")

In [5]: s = Supplier("Sup Plier", "[email protected]")

In [6]: c.name
Out[6]: 'Some Body'

In [7]: c.email
Out[7]: '[email protected]'

In [8]: s.name
Out[8]: 'Sup Plier'

In [9]: s.email
Out[9]: '[email protected]'

In [10]: c.all_contacts
Out[10]: [<__main__.Contact at 0x1e3f42bbb70>, <__main__.Supplier at 0x1e3f42c1278>]

In [11]: c.order("I need plier")
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-11-728826faab97> in <module>()
----> 1 c.order("I need plier")

AttributeError: 'Contact' object has no attribute 'order'

In [12]: s.order("I need plier")
If this were a real system we would send I need plier order to Sup Plier

In [13]: s.all_contacts
Out[13]: [<__main__.Contact at 0x1e3f42bbb70>, <__main__.Supplier at 0x1e3f42c1278>]

 參考：本文參考學習《Python3 Object Oriented Programming》，Dusty Phillips 著