Acts like twistd

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()