def postprocess_transformers(self) -> list[cirq.TRANSFORMER]:
        """List of transformers which should be run after decomposing individual operations."""

        def rewriter(o: cirq.CircuitOperation):
            result = self._decompose_single_qubit_operation(o, -1)
            return o.circuit.all_operations() if result is NotImplemented else result

        return [
            transformers.create_transformer_with_kwargs(
                transformers.merge_k_qubit_unitaries, k=1, rewriter=rewriter
            ),
            transformers.drop_negligible_operations,
            transformers.drop_empty_moments,
        ]
List of transformers which should be run after decomposing individual operations.
cirq-core/cirq/contrib/paulistring/clifford_target_gateset.py