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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 subcommand(self, command_name=None):
 """ Decorate a function as a subcommand. Use its arguments as the command-line arguments"""

        def wrapper(decorated):
            cmd_name = command_name or decorated.__name__
            subparser = self.subparsers.add_parser(cmd_name,
                                                   description=decorated.__doc__)
            for args, kwargs in describe_arguments(decorated):
                subparser.add_argument(*args, **kwargs)
            subparser.set_defaults(func=decorated)
            return decorated
        return wrapper