code: def ray_start(scope="module"):
      port = random.randint(MIN_DYNAMIC_PORT, MAX_DYNAMIC_PORT)
      subprocess.check_output(
          [
              "ray",
              "start",
              "--head",
              "--num-cpus",
              "16",
              "--ray-client-server-port",
              f"{port}",
          ]
      )
      try:
          yield f"localhost:{port}"
      finally:
          subprocess.check_output(["ray", "stop", "--force"])
  
imports: import os
  import random
  import subprocess
  import tempfile
  import pytest
  import requests
  import ray
  from ray import serve
  from ray._private.test_utils import wait_for_condition
  from ray._private.usage import usage_lib
  from ray.cluster_utils import AutoscalingCluster, Cluster
  from ray.serve._private import api
  from ray.serve._private.test_utils import TELEMETRY_ROUTE_PREFIX, check_ray_stopped
  from ray.serve.context import _get_global_client
  from ray.tests.conftest import propagate_logs, pytest_runtest_makereport
label_desc: Use image node_id 4 for calling a global function with example usage: ray_start(scope) without return types