code: def test_unmanaged_ray_hp_search() -> None:
      master_url = conf.make_master_url()
      exp_path = EXAMPLES_ROOT / "ray"
      runtime_env = {
          "env_vars": {
              "DET_MASTER": master_url,
          }
      }
  
      try:
          subprocess.run(
              ["ray", "start", "--head", "--disable-usage-stats"],
              check=True,
          )
          ray_utils.ray_job_submit(
              exp_path,
              ["python", "ray_hp_search.py"],
              submit_args=[
                  "--runtime-env-json",
                  json.dumps(runtime_env),
              ],
          )
      finally:
          subprocess.run(["ray", "stop"], check=True)
  
file_path: determined/e2e_tests/tests/experiment/test_unmanaged.py
imports: import json
  import os
  import subprocess
  from typing import List
  import pytest
  from tests import config
  from tests import ray_utils
label_desc: Use image node_id 4 for calling a global function with example usage: test_unmanaged_ray_hp_search() without return types