def __init__(self, db, timeout=3600, collection='tweepy_cache'):
        Cache.__init__(self, timeout)
        self.timeout = timeout
        self.col = db[collection]
        self.col.create_index('created', expireAfterSeconds=timeout)
Should receive a "database" cursor from pymongo.
dataset/ETHPy150Open tweepy/tweepy/tweepy/cache.py/MongodbCache.__init__