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 _on_item_widget_key_press_event(self, widget, event, item):
    if event.state & gtk.gdk.MOD1_MASK:     # Alt key
      key_name = gtk.gdk.keyval_name(event.keyval)
      if key_name in ["Up", "KP_Up"]:
        self.reorder_item(
          item, self._get_item_position(item) - 1)
      elif key_name in ["Down", "KP_Down"]:
        self.reorder_item(
          item, self._get_item_position(item) + 1)