text: # -*-coding:utf8-*-
  
  import sys
  reload(sys)
  sys.setdefaultencoding("utf-8")
  
  import redis
  
  red_queue = "thread_test_the_url_queue"
  red_crawled_set = "thread_test_url_has_crawled"
  
  # connect to redis server
  red = redis.Redis(host='localhost', port=6379, db=1)
  
  
  def re_crawl_url(url):
      red.lpush(red_queue, url)
  
  
  def check_url(url):
      if red.sadd(red_crawled_set, url):
          red.lpush(red_queue, url)