code: def tearDownClass(cls):
      ray.shutdown()
  
file_path: ray/python/ray/rllib/algorithms/dreamerv3/tests/test_dreamerv3.py
imports: import unittest
  import gymnasium
  import numpy
  import ray
  from ray.rllib.algorithms.dreamerv3 import dreamerv3
  from ray.rllib.policy.sample_batch import DEFAULT_POLICY_ID
  from ray.rllib.utils.numpy import one_hot
  from ray.rllib.utils.test_utils import framework_iterator
  from ray import tune
label_desc: Use image node_id 2 for calling the TestDreamerV3 obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types