def METHOD_NAME(backend_class):
    # Arrange
    settings = DisplacementSettings()
    value_a = 0.1
    value_b = 0.2
    weight = 0.25
    settings.courant_field_data = (
        np.array([[value_a, value_b]]).T,
        np.array([[0, 0]]),
    )
    settings.positions = [[weight], [0]]
    sut, particulator = settings.get_displacement(
        backend_class, scheme="ExplicitInSpace", adaptive=False
    )
    # Act
    sut.calculate_displacement(
        sut.displacement,
        sut.courant,
        particulator.attributes["cell origin"],
        particulator.attributes["position in cell"],
    )
    # Assert
    np.testing.assert_equal(
        sut.displacement[0, slice(0, 1)].to_ndarray(),
        (1 - weight) * value_a + weight * value_b,
    )