code: def test_request_hangs_in_assignment(ray_instance, shutdown_serve):
      """
      Verify that requests are timed out if they take longer than the timeout while
      pending assignment (queued in the handle).
      """
      signal_actor = SignalActor.remote()
  
      @serve.deployment(
          graceful_shutdown_timeout_s=0, max_concurrent_queries=1
      )
      class HangsOnFirstRequest:
          def __init__(self):
              self._saw_first_request = False
  
          async def __call__(self):
              await signal_actor.wait.remote()
              return "Success!"
  
      serve.run(HangsOnFirstRequest.bind())
  
      # First request will hang executing, second pending assignment.
      response_ref1 = do_request.remote()
      response_ref2 = do_request.remote()
  
      # Streaming path does not retry on timeouts, so the requests should be failed.
      assert ray.get(response_ref1).status_code == 408
      assert ray.get(response_ref2).status_code == 408
      ray.get(signal_actor.send.remote())
      assert ray.get(do_request.remote()).status_code == 200
  
imports: import asyncio
  import os
  import sys
  import time
  from typing import Generator, Set
  import pytest
  import requests
  from fastapi import FastAPI
  from starlette.requests import Request
  from starlette.responses import StreamingResponse
  import ray
  from ray import serve
  from ray._private.test_utils import SignalActor, wait_for_condition
  from ray.dashboard.modules.serve.sdk import ServeSubmissionClient
  from ray.serve._private.common import ApplicationStatus
  from ray.serve._private.test_utils import send_signal_on_cancellation
  from ray.serve.schema import ServeInstanceDetails
  from ray.util.state import list_tasks
label_desc: Use image node_id 6 for calling a global function with example usage: test_request_hangs_in_assignment(ray_instance, shutdown_serve) and returns: str