code: def test_context_manager(self):
      with select.epoll(16) as ep:
          self.assertGreater(ep.fileno(), 0)
          self.assertFalse(ep.closed)
      self.assertTrue(ep.closed)
      self.assertRaises(ValueError, ep.fileno)
  
imports: import errno
  import os
  import select
  import socket
  import time
  import unittest
  from test import support
label_desc: Use image node_id 6 for calling the TestEPoll obj's underlying member method code with example usage: obj.test_context_manager() without return types