能删单一的元素也能清空字典，清空只需一项操作 。
tinydict = {'Name': 'Zara', 'Age': 7, 'Class': 'First'}del tinydict['Name']# 删除键是'Name'的键值对tinydict.clear()# 清空字典所有条目del tinydict# 删除字典print(tinydict['Name']) # 由于不存在键值对，会报出KeyErrorprint "tinydict['Age']: ", tinydict['Age'] print "tinydict['School']: ", tinydict['School']
字典键的特性
字典值可以没有限制地取任何 p y t h o n对象，既可以是标准地对象，也可以是用户定义的，但键不行
tinydict = {'Name': 'Runoob', 'Age': 7, 'Name': 'Manni'} print "tinydict['Name']: ", tinydict['Name']# 运行结果tinydict['Name']:Manni
inydict = {['Name']: 'Zara', 'Age': 7} print "tinydict['Name']: ", tinydict['Name']# 运行结果TypeError: unhashable type: 'list'
try-语句块海象运算符列表推导式List的常用函数
简单的函数有：
接下的函数最好单独一行，不要出现print（list.()）这样的语句，会打印出None，而不是所期望的值 。
list1.(obj)
aList = [123, 'xyz', 'zara', 'abc']aList.append( 2009 )print ("Updated List : ", aList)# resultUpdated List :[123, 'xyz', 'zara', 'abc', 2009]
list2.count(obj)
aList = [123, 'xyz', 'zara', 'abc', 123]print ("Count for 123 : ", aList.count(123))print ("Count for zara : ", aList.count('zara'))# resultCount for 123 :2Count for zara :1
list3.count(obj)
list1 = [1,2,3,4]dict1 = {'a':1,'b':2}list1.extend(dict1)print(list1)# result[1, 2, 3, 4, 'a', 'b']aList = [123, 'xyz', 'zara', 'abc', 123]bList = [2009, 'manni']aList.extend(bList)print ("Extended List : ", aList)# resultExtended List :[123, 'xyz', 'zara', 'abc', 123, 2009, 'manni']
list4.index(x[, start[, end]])
aList = ['runoob', 'xyz', 'runoob', 'abc']print ("runoob 索引位置: ", aList.index( 'runoob' ))print ("runoob 索引位置 : ", aList.index( 'runoob', 1, 3 ))# resultrunoob 索引位置:0runoob 索引位置 :2
list5.()
aList = [123, 'xyz', 'zara', 'abc']blist = [1,2,3,5,6]aList.insert(3, blist)print("Final List : ", aList)# resultFinal List :[123, 'xyz', 'zara', [1, 2, 3, 5, 6], 'abc']
list6.pop()
list1 = ['Google', 'Runoob', 'Taobao']list_pop = list1.pop(1)print("删除的项为 :", list_pop)print("列表现在为 : ", list1)# result删除的项为 : Runoob列表现在为 :['Google', 'Taobao']
list7.()
aList = [123, 'xyz', 'zara', 'abc', 'xyz']aList.remove('xyz')print ("List : ", aList)aList.remove('abc')print ("List : ", aList)# resultList :[123, 'zara', 'abc', 'xyz']List :[123, 'zara', 'xyz']
list8.()
aList = [123, 'xyz', 'zara', 'abc', 'xyz']aList.reverse()print ("List : ", aList)# resultList :['xyz', 'abc', 'zara', 'xyz', 123]