code: def dynamodb2_server():
      host = "localhost"
      port = 5001
      url = "http://{host}:{port}".format(host=host, port=port)
      process = start_service("dynamodb2", host, port)
      yield url
      stop_process(process)
  
file_path: ray/python/ray/tests/mock_s3_server.py
imports: import pytest
  import requests
  import shutil
  import signal
  import subprocess
  import time
label_desc: Use image node_id 3 for calling a global function with example usage: dynamodb2_server() without return types