code: def tearDownClass(cls):
      cls.spark.stop()
  
imports: import os
  import shutil
  import unittest
  from pyspark.sql import SparkSession
  from pyspark.ml.torch.tests.test_distributor import TorchDistributorBaselineUnitTestsMixin, TorchDistributorLocalUnitTestsMixin, TorchDistributorDistributedUnitTestsMixin, TorchWrapperUnitTestsMixin, set_up_test_dirs, get_local_mode_conf, get_distributed_mode_conf
label_desc: Use image node_id 2 for calling the TorchDistributorBaselineUnitTestsOnConnect obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types