>>> range(1,20)? #代表從1到20(不包含20)
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]
>>> range(1,20,3)? #代表從1到20闽烙，間隔3(不包含20)
[1, 4, 7, 10, 13, 16, 19]
>>> range(1,20,4)? #代表從1到20寄纵，間隔4(不包含20)
[1, 5, 9, 13, 17]
>>> range(20)? #代表從0到20(不包含20)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]
