code: def tearDownClass(cls):
      ray.shutdown()
  
file_path: ray/rllib/tests/test_timesteps.py
imports: import numpy
  import unittest
  import ray
  import ray.rllib.algorithms.ppo
  from ray.rllib.examples.env.random_env import RandomEnv
  from ray.rllib.utils.test_utils import check, framework_iterator
label_desc: Use image node_id 2 for calling the TestTimeSteps obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types