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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 add_signaling_arguments(parser):
 """ Add signaling method arguments to an argparse.ArgumentParser. """

    parser.add_argument('--signaling', '-s', choices=[
        'copy-and-paste', 'tcp-socket', 'unix-socket'])
    parser.add_argument('--signaling-host', default='127.0.0.1',
                        help='Signaling host (tcp-socket only)')
    parser.add_argument('--signaling-port', default=1234,
                        help='Signaling port (tcp-socket only)')
    parser.add_argument('--signaling-path', default='aiortc.socket',
                        help='Signaling socket path (unix-socket only)')