code: def setUpClass(cls):
      ray.init()
  
imports: from collections import Counter
  import unittest
  import ray
  from ray.rllib.algorithms.callbacks import DefaultCallbacks, make_multi_callbacks
  import ray.rllib.algorithms.dqn
  from ray.rllib.algorithms.ppo import PPOConfig
  from ray.rllib.evaluation.episode import Episode
  from ray.rllib.examples.env.random_env import RandomEnv
  from ray.rllib.utils.test_utils import framework_iterator
label_desc: Use image node_id 1 for calling the TestCallbacks obj's underlying member method code with example usage: obj.setUpClass(cls) without return types