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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 update(self, _attributes=None, **attributes):
 """ Update the parent model on the relationship. :param attributes: The update attributes :type attributes: dict :rtype: mixed """

        if _attributes is not None:
            attributes.update(_attributes)

        instance = self.get_results()

        return instance.fill(attributes).save()