def save_last_sync(self, ids, process):
        try:
            spec = {'_id': 'last_sync'}
            document = {'$set': {process: ids}}
            self.db.internal.update(spec, document, upsert=True)
        except Exception as e:
            raise DatabaseException(e)
def _update_width(self, width_diff):
    if self._items_total_width is None:
      self._items_total_width = self.get_allocation().width