IPv6 压缩地址格式转首选地址格式 python 2.7

#coding=utf-8
from __future__ import print_function
import sys

def bu0(dizhi):
    dizhi1 = dizhi.split(':')
    for i in range(0, len(dizhi1)):
        # 小段地址补0 如 :AB: 补成:00AB:
        if ((len(dizhi1[i]) < 4) and (len(dizhi1[i]) > 0)) :
            temp = dizhi1[i]
        # 需补0数 que0
            que0 = 4 - len(dizhi1[i])
            temp2 =  "".join('0' for i in range(0, que0))
            dizhi1[i] = temp2 + temp

    # 补 ::中的0
    # count 为补完:中0后长度
    count = 0
    for i in range(0, len(dizhi1)):
        count = count + len(dizhi1[i])
    count = 32 - count
    aa = []
    aa = ''.join('0' for i in range(0, count))
    for i in range(1, len(dizhi1)-1):
        if len(dizhi1[i])==0 :
            dizhi1[i] = aa
    for i in range(len(dizhi1)):
        bb = ''.join(sttt for sttt in dizhi1)
    return bb

def legal(dizhi):
    d