枚举

li = ['a','b','c','d']

for index,i in enumerate(li): #for index,i in enumerate(li,100):
print(index,i) #print(index,i)

结果 0 a # 结果 100 a
1 b # 101 b
2 c # 102 c
3 d # 103 d
li后面加,数字变为数字开头的排序