message.py 文件源码

def _set_uuid(self, uuid):
        if uuid is None:
            # UUID generation is expensive.  Using FastUUID instead of the built
            # in UUID methods increases Messages that can be instantiated per
            # second from ~25,000 to ~185,000.  Not generating UUIDs at all
            # increases the throughput further still to about 730,000 per
            # second.
            uuid = self._fast_uuid.uuid4()
        elif len(uuid) != 16:
            raise TypeError(
                "UUIDs should be exactly 16 bytes.  Conforming UUID's can be "
                "generated with `import uuid; uuid.uuid4().bytes`."
            )
        self._uuid = uuid