code: def test_proactor_win_policy(self):
      async def main():
          self.assertIsInstance(
              asyncio.get_running_loop(), asyncio.ProactorEventLoop
          )
  
      old_policy = asyncio.get_event_loop_policy()
      try:
          asyncio.set_event_loop_policy(
              asyncio.WindowsProactorEventLoopPolicy()
          )
          asyncio.run(main())
      finally:
          asyncio.set_event_loop_policy(old_policy)
  
imports: import os
  import signal
  import socket
  import sys
  import time
  import threading
  import unittest
  from unittest import mock
  import _overlapped
  import _winapi
  import asyncio
  from asyncio import windows_events
  from test.test_asyncio import utils
label_desc: Use image node_id 2 for calling the WinPolicyTests obj's underlying member method code with example usage: obj.test_proactor_win_policy() without return types