Python之验证码面试题

import random

ret = ''
for i in range(4):
    num = str(random.randint(0, 9))
    alpha = chr(random.randint(65, 90))
    alpha_c = chr(random.randint(97, 122))
    rc = random.choice([num, alpha, alpha_c])
    ret += rc

print(ret)