enumerate()

# 将数组元素和index合并输出
l = [1,2,3,4]
for i, x in enumerate(l):
	print(f"{i} + {x}")

zip

# 将多个数组压缩
a = [1,2,3]
b = [2,3,4]
c = [3,4,5]
d = zip(a,b,c)

Counter

# 将数组中的各种元素统计成字典
l = [1,2,2,1,3]
di = Counter(l)

sorted

# 自定义排序
l = sorted([4,3,2,1],key=lambda x : -x) # 升序

bisect_left

import bisect
s = [1,2,3,4,4,4,5,6]
#	[0,1,2,3,4,5,6,7]
bisect.bisect_left(s,4)
#print -> 3 

bisect_right

import bisect
s = [1,2,3,4,4,4,5,6]
#   [0,1,2,3,4,5,6,7]
bisect.bisect_right(s,4)
#print -> 6