def __nonzero__(self):
        return bool(
            self.timeline
            or self.state
            or self.ephemeral
            or self.account_data
            # nb the notification count does not, er, count: if there's nothing
            # else in the result, we don't need to send it.
        )
Make the result appear empty if there are no updates. This is used
dataset/ETHPy150Open matrix-org/synapse/synapse/handlers/sync.py/JoinedSyncResult.__nonzero__