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 range(cls, dataset, dimension):
        dimension = dataset.get_dimension(dimension, strict=True)
        column = dataset.data[dimension.name]
        if dimension.nodata is not None:
            column = cls.replace_value(column, dimension.nodata)
        if column.dtype.kind == 'O':
            return np.NaN, np.NaN
        else:
            return finite_range(column, column.min(), column.max())