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 _expandsets(kindpats, ctx):
    """Returns the kindpats list with the 'set' patterns expanded."""
    fset = set()
    other = []

    for kind, pat, source in kindpats:
        if kind == "set":
            if not ctx:
                raise error.ProgrammingError("fileset expression with no " "context")
            s = ctx.getfileset(pat)
            fset.update(s)
            continue
        other.append((kind, pat, source))
    return fset, other