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 __getitem__(self, key):
        value = self._collection[key]
        if isinstance(key, slice):
            slice_repr = ":".join(str("" if i is None else i) for i in (key.start, key.stop, key.step))
            logger.debug("Get /%s[%s] config key", "/".join(self._path), slice_repr)
            return [self._to_python(item) for item in value]
        else:
            logger.debug("Get /%s[%s] config key", "/".join(self._path), key)
            return self._to_python(value)