Python元字典
字典(dictionary)是除列表以外python之中最靈活的內置數據結構類型。列表是有序的對象結合，字典是無序的對象集合。
兩者之間的區別在于：字典當中的元素是通過鍵來存取的，而不是通過偏移存取。
字典用"{ }"標識。字典由索引(key)和它對應的值value組成。
#!/usr/bin/python# -*- coding: UTF-8 -*-dict = {}dict['one'] = "This is one"dict[2] = "This is two"tinydict = {'name': 'john','code':6734, 'dept': 'sales'}print dict['one'] # 輸出鍵為'one' 的值print dict[2] # 輸出鍵為 2 的值print tinydict # 輸出完整的字典print tinydict.keys() # 輸出所有鍵print tinydict.values() # 輸出所有值輸出結果為：
This is one This is two {'dept': 'sales', 'code': 6734, 'name': 'john'} ['dept', 'code', 'name'] ['sales', 6734, 'john']Python成員運算符
除了以上的一些運算符之外，Python還支持成員運算符，測試實例中包含了一系列的成員，包括字符串，列表或元組。
以下實例演示了Python所有成員運算符的操作：
#!/usr/bin/pythona = 10b = 20list = [1, 2, 3, 4, 5 ];if ( a in list ): print "Line 1 - a is available in the given list"else: print "Line 1 - a is not available in the given list"if ( b not in list ): print "Line 2 - b is not available in the given list"else: print "Line 2 - b is available in the given list"a = 2if ( a in list ): print "Line 3 - a is available in the given list"else: print "Line 3 - a is not available in the given list"
以上實例輸出結果：
Line 1 - a is not available in the given listLine 2 - b is not available in the given listLine 3 - a is available in the given list
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