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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_or_create_model_key(self):
 """ Get or create key for the model. Returns ~~~~~~~ (model_key, boolean) tuple """

        model_cache_info = model_cache_backend.retrieve_model_cache_info(self.model._meta.db_table)
        if not model_cache_info:
            return uuid.uuid4().hex, True
        return model_cache_info.table_key, False