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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 touch(self):
 """ Touch all of the related models of the relationship. """

        key = self.get_related().get_key_name()

        columns = self.get_related_fresh_update()

        ids = self.get_related_ids()

        if len(ids) > 0:
            self.get_related().new_query().where_in(key, ids).update(columns)