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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_daemon():
 """ Start a thread to continuously read log files and append lines in DB. Work in progress. Currently the thread doesn't append anything, it only print the information parsed from each line read. Returns: thread: the started thread. """

        if RequestLog.daemon is None:
            parser = get_nginx_parser()
            RequestLog.daemon = RequestLog.ParseToDBThread(parser, daemon=True)
        RequestLog.daemon.start()
        return RequestLog.daemon