python基本语法3.2--字典的操作

 1 d = {'a': 1, 'b': 2, 1: 'one', 2: 'two', 3: [1, 2, 3]}
 2 print(type(dict))
 3 print(type(d))
 4 print(d)
 5 
 6 # 访问元素
 7 print(d['a'])
 8 print(d[1])
 9 print(d[3])
10 
11 # 判断key是否存在
12 print('two' in d)
13 print(3 in d)
14 del(d[3])   # del(dict[key])
15 
16 print(len(d))
17 d[3] = [1, 2, 3, 4]
18 d[3] = '1234'
19 
20 # 遍历
21 for key in d:
22     print(d[key])
23 for k, v in d.items():
24     print(k,v)
25 
26 keys = d.keys()
27 print(type(keys))
28 print(keys)