1、成员方法
增:append、extend、insert
删:pop、remove
查:index、count
排序:reverse、sort
(1)a[::2] == [1, 3, 5]; a[-2:] == [4, 5]
(2)sum(map(lambda x: x + 3, a[1::2]))
(3)
import random
def l2dict(a):
random.shuffle(a)
b = sorted(a)
d = {}
for i in range(len(a)):
d[a] = b
return d