def __init__(self, cache, key, subFactory, extraWork):

        self.cache = cache
        self.key = key
        self.subFactory = subFactory
        self.finishedExtraWork = False
        self.extraWork = extraWork
@param cache: a Q2QService
dataset/ETHPy150Open twisted/vertex/vertex/conncache.py/_CachingClientFactory.__init__