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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 open_args(subparsers):
 """ The `mp open` command will open a resource with the system application, such as Excel or OpenOffice """

    parser = subparsers.add_parser(
        'open',
        help='open a CSV resoruce with a system application',
        description=open_args.__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )

    parser.set_defaults(run_command=open_cmd)

    parser.add_argument('metatabfile', nargs='?',
                        help="Path or URL to a metatab file. If not provided, defaults to 'metadata.csv' ")

    return parser