#! /usr/bin/env python3

import random

checkcode = ""

## 全部为数字的验证码

# for i in range(4):

#     current = random.randrange(0,6)

#     checkcode += str(current)

# print(checkcode)

## 有数字、字母的验证码

for i in range(6):

    current = random.randrange(0, 4)   ## 类似于[start, end)

    if current == i:

        tmp = chr(random.randint(65, 90))  ##等价于 random.randrange(65, 91)

    else:

        tmp = random.randint(0, 9)

    checkcode += str(tmp)

print(checkcode)