def METHOD_NAME(self, table, key, data):
    table = table.upper()
    config = self.get_config()
    if data is None:
        self._del_key(config, table, key)
    else:
        table_data = config.setdefault(table, {})
        curr_data = table_data.setdefault(key, {})
        curr_data.update(data)
    self._write_config(config)