1. byte类型以字节存储数据

    list列表长度可变，可以进行修改、切片、追加、删除、嵌套、迭代、成员判断等操作

    1. code ```python s = “this is a book” s = s.replace(‘book’, ‘apple’) print(s.startwith(‘this’)) print(s.endwith(‘apple’))

    if s[-1] == ‘@’: s = s[:-1]

    2. 3. code
    3. ```python
    4. li = [2, 5, 6, 4, 9, 10, 23]
    5. print(li[::-1])
    6. print(sorted(li, reverse=True)[::2])