>>> #切片的要素,起始偏移量终止偏移量和步长
>>> a=[18,48,8,68]
>>> a[:]
[18, 48, 8, 68]
>>> a[2】
SyntaxError: invalid character in identifier
>>> a[2]
8
>>> a[2:]
[8, 68]
>>> a[2:3]
[8]
>>> a[:2]
[18, 48]
>>> a[::2]
[18, 8]
>>>
>>> #切片的要素,起始偏移量终止偏移量和步长
>>> a=[18,48,8,68]
>>> a[:]
[18, 48, 8, 68]
>>> a[2】
SyntaxError: invalid character in identifier
>>> a[2]
8
>>> a[2:]
[8, 68]
>>> a[2:3]
[8]
>>> a[:2]
[18, 48]
>>> a[::2]
[18, 8]
>>>