def METHOD_NAME(self):
    """Test the base case for the Grover operator."""
    with self.subTest("single Z oracle"):
        oracle = QuantumCircuit(3)
        oracle.z(2)  # good state if last qubit is 1
        grover_op = GroverOperator(oracle)
        self.assertGroverOperatorIsCorrect(grover_op, oracle)
    with self.subTest("target state x0x1"):
        oracle = QuantumCircuit(4)
        oracle.x(1)
        oracle.z(1)
        oracle.x(1)
        oracle.z(3)
        grover_op = GroverOperator(oracle)
        self.assertGroverOperatorIsCorrect(grover_op, oracle)