代码如下：

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
__author__ = 'junxi'

import random
checkcode = ''
for i in range(4):
    current = random.randrange(0,4)
    if current != i:
        temp = chr(random.randint(65,90))    # chr返回整数对应的ascll字符
        print temp
    else:
        temp = random.randint(0,9)
    checkcode += str(temp)
print(checkcode)

运行：

02V1