def METHOD_NAME(self):
    with pytest.raises(sc.DimensionError) as e_info:
        self._d['a'][
            'x', 1.5 * sc.units.dimensionless : 4.5 * sc.units.dimensionless
        ] = sc.Variable(dims=['x'], values=[6.0, 6.0], unit=sc.units.m)
    assert str(e_info.value) == 'Expected (x: 3) to include (x: 2).'