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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(self):
 """ Definition and addition of all arguments. """

        if self.parser is None:
            raise TypeError("Parser cannot be None, has create_parser been called?")

        for keys, kwargs in self.args.items():
            if not isinstance(keys, tuple):
                keys = (keys,)
            self.parser.add_argument(*keys, **kwargs)