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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_model(self, ids):
 """ Gets the model for the specified motors. """

        to_get_ids = [i for i in ids if i not in self._known_models]
        models = [dxl_to_model(m) for m in self._get_model(to_get_ids, convert=False)]
        self._known_models.update(zip(to_get_ids, models))

        return tuple(self._known_models[id] for id in ids)