code: def sync_to_worker_if_possible(self):
          
          if self.worker_ip == self.local_ip:
              return
          ssh_key = get_ssh_key()
          ssh_user = get_ssh_user()
          global _log_sync_warned
          if ssh_key is None or ssh_user is None:
              if not _log_sync_warned:
                  logger.error("Log sync requires cluster to be setup with "
                               "`ray up`.")
                  _log_sync_warned = True
              return
          if not distutils.spawn.find_executable("rsync"):
              logger.error("Log sync requires rsync to be installed.")
              return
          source = "{}/".format(self.local_dir)
          target = "{}@{}:{}/".format(ssh_user, self.worker_ip, self.local_dir)
          final_cmd = (("""rsync -savz -e "ssh -i {} -o ConnectTimeout=120s """
                        """-o StrictHostKeyChecking=no" {} {}""").format(
                            quote(ssh_key), quote(source), quote(target)))
          logger.info("Syncing results to %s", str(self.worker_ip))
          sync_process = subprocess.Popen(
              final_cmd, shell=True, stdout=self.logfile)
          sync_process.wait()
docs: Syncs the local logdir on driver to worker if possible.
  
          Requires ray cluster to be started with the autoscaler. Also requires
          rsync to be installed.