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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 get_subparser(self, name):
 """ Convenience method to get a certain subparser Parameters name: str The name of the subparser Returns ------- FuncArgParser The subparsers corresponding to `name` """

        if self._subparsers_action is None:
            raise ValueError("%s has no subparsers defined!" % self)
        return self._subparsers_action.choices[name]