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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 argset(name, *args, **kwargs):
 """ Decorator to add sets of required mutually exclusive args to subcommands. """

    def _arg(f):
        if not hasattr(f, '_subcommand_argsets'):
            f._subcommand_argsets = {}
        f._subcommand_argsets.setdefault(name, []).append((args, kwargs))
        return f
    return _arg