code: def tearDownClass(cls):
      if cls.orig_value is not None:
          os.environ["MONAI_DEBUG"] = cls.orig_value
      else:
          os.environ.pop("MONAI_DEBUG")
      print("MONAI debug value:", str(MONAIEnvVars.debug()))
      super(__class__, cls).tearDownClass()
  
file_path: MONAI/tests/test_monai_env_vars.py
imports: from __future__ import annotations
  import os
  import unittest
  from monai.utils.misc import MONAIEnvVars
label_desc: Use image node_id 2 for calling the TestMONAIEnvVars obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types