随机生成mac地址

#!/usr/bin/python
# -*- coding: utf-8 -*-
import sys
import string
import random
num=int(sys.argv[1])

#随机生成一个MAC地址
def creat_mac():
    MAC='41-AF'
    hex_num=string.hexdigits
    for i in range(4):
        n=random.sample(hex_num,2)
        sn='-'+''.join(n).upper()
        MAC+=sn
    return MAC

#随机生成n个
def creat_mac1():
    with open('mac.txt','w')as f:
        for i in range(num):
            mac=creat_mac()
            print(mac)
            f.write(mac+'\n')
creat_mac1()