for i in {k: v for k, v in zip(range(10,40,10), range(3))}:  # 默认遍历keys()
    print(i)
for i in {k: v for k, v in zip(range(10,40,10), range(3))}.items():  # 遍历元组
    print(i)
{k: v for k, v in zip(range(10,30,10), range(30))}  # 根据键名多少来生成配对,超过键名个数的键值被忽略

10
20
30
(10, 0)
(20, 1)
(30, 2)
{10: 0, 20: 1}