def _create_connection(self, mode):
        if not self._started:
            self._start()
        if mode is _WRITER:
            return self._writer_engine.connect()
        elif self.synchronous_reader or mode is _ASYNC_READER:
            return self._reader_engine.connect()
        else:
            return self._writer_engine.connect()
dataset/ETHPy150Open openstack/oslo.db/oslo_db/sqlalchemy/enginefacade.py/_TransactionFactory._create_connection/original