code: def start(track_file,
            twitter_api_key,
            twitter_api_secret,
            twitter_access_token,
            twitter_access_token_secret,
            poll_interval=15,
            unfiltered=False,
            languages=None,
            debug=False,
            outfile=None):
      
      listener = construct_listener(outfile)
      checker = BasicFileTermChecker(track_file, listener)
  
      auth = get_tweepy_auth(twitter_api_key,
                             twitter_api_secret,
                             twitter_access_token,
                             twitter_access_token_secret)
  
      stream = DynamicTwitterStream(auth, listener, checker, unfiltered=unfiltered, languages=languages)
  
      set_terminate_listeners(stream)
      if debug:
          set_debug_listener(stream)
  
      begin_stream_loop(stream, poll_interval)
docs: Start the stream.