def test_drop_obs_column():
    adata = ad.AnnData(np.array(X_list), obs=obs_dict, dtype="int32")

    subset = adata[:2]
    assert subset.is_view
    # returns a copy of obs
    assert subset.obs.drop(columns=["oanno1"]).columns.tolist() == ["oanno2", "oanno3"]
    assert subset.is_view
    # would modify obs, so it should actualize subset and not modify adata
    subset.obs.drop(columns=["oanno1"], inplace=True)
    assert not subset.is_view
    assert subset.obs.columns.tolist() == ["oanno2", "oanno3"]

    assert adata.obs.columns.tolist() == ["oanno1", "oanno2", "oanno3"]
def test_parse_sections():
    simple_mariofile_sections = dict(mariofile.parse_sections(SIMPLE_MARIOFILE.splitlines(True)))
    assert len(simple_mariofile_sections) == 3
    complex_mariofile_sections = dict(mariofile.parse_sections(COMPLEX_MARIOFILE.splitlines(True)))
    assert len(complex_mariofile_sections) == 2
    assert sorted(complex_mariofile_sections.keys()) == ['DEFAULT', 'section']
    assert complex_mariofile_sections['DEFAULT'] == ['default text\n', '\n']
    with pytest.raises(mariofile.ConfigurationFileError):
        dict(mariofile.parse_sections(GARBAGE_MARIOFILE.splitlines(True)))
    with pytest.raises(mariofile.ConfigurationFileError):
        dict(mariofile.parse_sections(INVALID_SECTION_MARIOFILE.splitlines(True)))
    more_complex_mariofile_sections = dict(
            mariofile.parse_sections(MORE_COMPLEX_MARIOFILE.splitlines(True))
    )
    more_complex_mariofile_sections_keys = ['DEFAULT', 'section_one', 'section_two', 'three']
    assert sorted(more_complex_mariofile_sections.keys()) == more_complex_mariofile_sections_keys
    assert more_complex_mariofile_sections['three'] == []