def to_json(self):
    return {"filename": self._filename}
Modifier to return a core Connection object instead of Session.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/mapreduce/output_writers.py/FileOutputWriterBase.to_json--crossover with--dataset/ETHPy150Open openstack/oslo.db/oslo_db/sqlalchemy/enginefacade.py/_TransactionContextManager.connection