code: def setup_class(cls):
      cls.loop = tornado.ioloop.IOLoop()
      cls.loop.make_current()
      cls.thread = threading.Thread(target=cls.loop.start)
      cls.thread.daemon = True
      cls.thread.start()
  
imports: import queue
  import random
  import threading
  from functools import partial
  import tornado.ioloop
  from perspective import PerspectiveError, PerspectiveManager, Table
  from pytest import raises
label_desc: Use image node_id 1 for calling the TestAsync obj's underlying member method code with example usage: obj.setup_class(cls) without return types