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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 query_ids(self, ids):
 """ Query by list of identifiers """


        results = self._get_repo_filter(Layer.objects).filter(uuid__in=ids).all()

        if len(results) == 0:  # try services
            results = self._get_repo_filter(Service.objects).filter(uuid__in=ids).all()

        return results