用python查找未注册的域名

#-*- encoding: utf-8 -*-  
import sys
reload(sys)
sys.setdefaultencoding("utf-8")

import urllib
import urllib2
import time, threading


l='abcdefghijklmnopqrstuvwxyz0123456789-'
fl=open('d:\\reg.txt','a')
#step是上次扫描到的位置
step='aao9'
t=False
for i in l:
    for j in l:
        for k in l:
            for m in l:
                if i=='-':
                    continue
                if m=='-':
                    continue
                s=i+j+k+m
                if s==step:
                    t=True
                if t==True:
                    url = 'http://vip.regsky.com/reg/domainquery.asp?domainname='+s+'%2Ecom'
                    response = urllib2.urlopen(url)
                    the_page = response.read()
                    if the_page=='Y':
                        print s+":Not reged!"
                        f=open('c:\\reg.txt','a')
                        f.write(s+" :Not reged!\r\n")
                        f.close()
                    else:
                        print s +": Reged!"
                        fl.write(s +": Reged!\r\n")
                    #线程休息3秒钟，别被服务器屏蔽了
                    time.sleep(3)

fl.close()