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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 spawn(opts, conf):
 """ Acts like twistd """

    if opts.config is not None:
        os.environ["CALLSIGN_CONFIG_FILE"] = opts.config
    sys.argv[1:] = [
        "-noy", sibpath(__file__, "callsign.tac"),
        "--pidfile", conf['pidfile'],
        "--logfile", conf['logfile'],
    ]
    twistd.run()