code: def test_debug_mode(self):
      with self.call_init(mode="debug") as exp:
          exp["some/variable"] = 13
          self.assertEqual(13, exp["some/variable"].fetch())
          self.assertNotIn(str(exp._id), os.listdir(".neptune"))
  
imports: import contextlib
  import os
  import time
  import unittest
  from abc import abstractmethod
  from io import StringIO
  from unittest.mock import Mock
  from neptune.exceptions import MetadataInconsistency, MissingFieldException, NeptuneOfflineModeFetchException, NeptuneSynchronizationAlreadyStoppedException, TypeDoesNotSupportAttributeException
label_desc: Use image node_id 3 for calling the AbstractExperimentTestMixin obj's underlying member method code with example usage: obj.test_debug_mode() without return types