Scrip

class ThreadClass(threading.Thread):
    def __init__(self, user):
        self.user = user
        threading.Thread.__init__(self)
        time.sleep(0.2)

    def run(self):
        action = openurl('http://a-website.com/management.php?action='+USER_ID+'&categ='+self.user+'&do=5', "ok=1").read()
        if "error" in action:
            x = 1
            while x == 1:
               action = openurl('http://a-website.com/management.php?action='+USER_ID+'&categ='+self.user+'&do=5', "ok=1").read()
               if "Please click" in action:
                   x = 0

        time.sleep(0.2)



for i in range(len(users)):
  t = ThreadClass(users[i])
  t.start()