python基本语法3.2--字典的操作

d = {'a': 1, 'b': 2, 1: 'one', 2: 'two', 3: [1, 2, 3]}
print(type(dict))
print(type(d))
print(d)

# 访问元素
print(d['a'])
print(d[1])
print(d[3])

# 判断key是否存在
print('two' in d)
print(3 in d)
del(d[3])   # del(dict[key])

print(len(d))
d[3] = [1, 2, 3, 4]
d[3] = '1234'

# 遍历
for key in d:
    print(d[key])
for k, v in d.items():
    print(k,v)

keys = d.keys()
print(type(keys))
print(keys)