def connect(self): 
        try:
            self.connection = pymongo.Connection(self.host, self.port)
            self.db = self.connection[self.name]
        except AutoReconnect:
            raise DatabaseException("It's not possible connect to the database")
def queue_when_in_transaction(call):
    if transaction_states[call.using]:
        transaction_states[call.using].push((call, (), {}))
    else:
        return call()