code: def __get_payload(self, uuid, failed):
          
          # Caller should have the publish_uuid_store lock
          try:
              return self.publish_uuid_store[uuid]
          except Exception as exc:
              msg = "Failed to load payload from publish store for UUID %s, %s: %s"
              if uuid in failed:
                  log.error(msg, uuid, "discarding", str(exc))
                  self.__discard_publish_uuid(uuid, failed)
              else:
                  log.error(msg, uuid, "will try agan", str(exc))
                  failed.add(uuid)
          return None
docs: Retry reading a message from the publish_uuid_store once, delete on the second failure.