code: def test_server():
      with cleanup_subprocesses(strict=True):
          server = fos.ServerService(5151)
          server.start()
          p = wait_for_subprocess(lambda p: "main.py" in p.cmdline())
          assert p.is_running()
          res = get_json_retry("http://127.0.0.1:5151/fiftyone")
          assert res["version"] == foc.VERSION
          server.stop()
          assert not p.is_running()
  
imports: from contextlib import contextmanager
  import os
  import sys
  import time
  import unittest
  import psutil
  import requests
  import retrying
  import fiftyone
  import fiftyone.constants
  import fiftyone.core.service
  import fiftyone.service.util
label_desc: Use image node_id 9 for calling a global function with example usage: test_server() without return types