def METHOD_NAME(self):
    self.cube.coord('air_pressure').standard_name = 'altitude'
    self.cube.coord('altitude').var_name = 'alt'
    self.cube.coord('altitude').long_name = 'altitude'
    self.cube.coord('altitude').units = 'm'
    assert not self.cube.coords('air_pressure')
    assert self.cube.coords('altitude')
    result = extract_levels(self.cube, [1, 2],
                            'linear_extrapolate',
                            coordinate='air_pressure')
    assert result.coords('air_pressure')
    assert not result.coords('altitude')
    assert result.shape == (2, 2, 2, 2)
    np.testing.assert_allclose(result.coord('air_pressure').points,
                               [1.0, 2.0])