def METHOD_NAME():
    for h in ts1.halos:
        db.get_default_session().delete(h) # remove previous objects so that we can add them afresh
    adder = add_simulation.SimulationAdderUpdater(sim.get_output_handler())
    adder.add_objects_to_timestep(ts1)
    importer = property_importer.PropertyImporter()
    importer.parse_command_line("Mvir Rvir hostHalo childHalo --for test_stat_files".split())
    print(importer.options)
    importer.run_calculation_loop()
    npt.assert_almost_equal(ts1.halos[0]["Rvir"], 195.87)
    npt.assert_almost_equal(ts1.halos[0]["Mvir"], 5.02432e+11)
    with npt.assert_raises(KeyError):
        ts1.halos[0]['hostHalo']
    with npt.assert_raises(KeyError):
        ts1.halos[1]['childHalo']
    assert ts1.halos[2]['hostHalo']==ts1.halos[0]
    assert ts1.halos[3]['hostHalo']==ts1.halos[0]
    testing.assert_halolists_equal(ts1.halos[0]['childHalo'], [ts1.halos[2], ts1.halos[3]])