def proto_decref(self, objectID):
        """
        (internal) Decrement the reference count of an object.

        If the reference count is zero, it will free the reference to this
        object.

        @param objectID: The object ID.
        """
        if isinstance(objectID, unicode):
            objectID = objectID.encode('utf8')
        refs = self.localObjects[objectID].decref()
        if refs == 0:
            puid = self.localObjects[objectID].object.processUniqueID()
            del self.luids[puid]
            del self.localObjects[objectID]
            self._localCleanup.pop(puid, lambda: None)()

        (internal) Decrement the reference count of an object.

        If the reference count is zero, it will free the reference to this
        object.

        @param objectID: The object ID.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/spread/pb.py