def _SleepTime(self, total, limit, duration):
    if not limit:
      return 0.0
    return max(0.0, (total / limit) - duration)
Serialize a dictionary into an hstore literal.  Keys and values must
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/remote_api/throttle.py/Throttle._SleepTime--crossover with--dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/dialects/postgresql/hstore.py/_serialize_hstore