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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 _hydrate_pivot_relation(self, models):
 """ Hydrate the pivot table relationship on the models. :type models: list """

        for model in models:
            pivot = self.new_existing_pivot(self._clean_pivot_attributes(model))

            model.set_relation("pivot", pivot)