def METHOD_NAME(self, interface):
    """Tests that create_initial_state works with a state-prep operation."""
    prep_op = self.DefaultPrep(qml.math.array([1 / 2] * 4, like=interface), wires=[0, 1])
    state = create_initial_state([0, 1], prep_operation=prep_op)
    assert qml.math.allequal(state, [1 / 2] * 4)
    assert qml.math.get_interface(state) == interface