def get_next_id(self):
        try:
            query = {'_id': 'last_id'}
            update = {'$inc': {'id': 1}}
            fn = self.db.internal.find_and_modify
            row = fn(query, update, upsert=True, new=True)
        except Exception as e:
            raise DatabaseException(e)
        return row['id']
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)