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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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):
 """Start the stream."""

    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)