def METHOD_NAME(observations_cta, phase_bkg_maker):
    maker = SpectrumDatasetMaker()
    e_reco = MapAxis.from_edges(np.logspace(0, 2, 5) * u.TeV, name="energy")
    e_true = MapAxis.from_edges(np.logspace(-0.5, 2, 11) * u.TeV, name="energy_true")
    radius = Angle(0.2, "deg")
    region = CircleSkyRegion(POS_VELA, radius)
    geom = RegionGeom.create(region=region, axes=[e_reco])
    dataset_empty = SpectrumDataset.create(geom=geom, energy_axis_true=e_true)
    obs = observations_cta[0]
    dataset = maker.run(dataset_empty, obs)
    dataset_on_off = phase_bkg_maker.run(dataset, obs)
    assert_allclose(dataset_on_off.acceptance, 0.1)
    assert_allclose(dataset_on_off.acceptance_off, 0.3)
    assert_allclose(dataset_on_off.counts.data.sum(), 28)
    assert_allclose(dataset_on_off.counts_off.data.sum(), 57)