#!/usr/bin/python env

# coding:utf-8

import random

def code(num=6):

    res = ""

    for i in range(num):

        # 数字0-9

        num1 = str(random.randint(0, 9))

        # 大写字母A-Z

        # a = chr(random.randint(65, 90))

        # 小写字母a-z

        # b = chr(random.randint(97, 122))

        # res += random.choice([num1, b])

        res += random.choice([num1])

    return res

a = code()

print(a)