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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_arguments(cls, parser, sys_arg_list=None):
 """ Arguments for the configfile mode. """

        parser.add_argument('-f', '--file', dest='file', required=True,
                            help="config file for routing groups "
                                 "(only in configfile mode)")
        return ["file"]