code: def _test_simple_ventilation(self, pool_class_factory):
      pool = pool_class_factory()
  
      items_to_ventilate = [{"item": i} for i in range(50)]
      ventilator = ConcurrentVentilator(
          ventilate_fn=pool.ventilate,
          items_to_ventilate=items_to_ventilate,
      )
      pool.start(IdentityWorker, ventilator=ventilator)
  
      all_results = [pool.get_results() for _ in items_to_ventilate]
      self.assertEqual(
          [i["item"] for i in items_to_ventilate], sorted(all_results)
      )
  
      pool.stop()
      pool.join()
  
imports: import time
  import unittest
  from petastorm.workers_pool import EmptyResultError
  from petastorm.workers_pool.dummy_pool import DummyPool
  from petastorm.workers_pool.process_pool import ProcessPool
  from petastorm.workers_pool.tests.stub_workers import IdentityWorker
  from petastorm.workers_pool.thread_pool import ThreadPool
  from petastorm.workers_pool.ventilator import ConcurrentVentilator
label_desc: Use image node_id 1 for calling the TestWorkersPool obj's underlying member method code with example usage: obj._test_simple_ventilation(pool_class_factory) without return types