code: def test_incorrect_config_file_backed_up(self):
      # create an incorrect config file at the correct location
      makedirs(NiftyNetGlobalConfigTestBase.config_home)
      incorrect_config = "\n".join(
          [
              NiftyNetGlobalConfigTestBase.header,
              "invalid_home_tag = ~/niftynet",
          ]
      )
      with open(
          NiftyNetGlobalConfigTestBase.config_file, "w"
      ) as config_file:
          config_file.write(incorrect_config)
  
      # the following should back it up and replace it with default config
      global_config = NiftyNetGlobalConfig().setup()
  
      self.assertTrue(isfile(NiftyNetGlobalConfigTestBase.config_file))
      self.assertEqual(
          global_config.get_niftynet_config_folder(),
          NiftyNetGlobalConfigTestBase.config_home,
      )
  
      # check if incorrect file was backed up
      found_files = glob(
          join(
              NiftyNetGlobalConfigTestBase.config_home,
              NiftyNetGlobalConfigTestBase.typify("config-backup-*"),
          )
      )
      self.assertTrue(len(found_files) == 1)
      with open(found_files[0], "r") as backup_file:
          self.assertEqual(backup_file.read(), incorrect_config)
  
      # cleanup: remove backup file
      NiftyNetGlobalConfigTestBase.remove_path(found_files[0])
  
imports: from glob import glob
  from os import remove, makedirs
  from os.path import expanduser, join, isdir, isfile
  from os.path import getmtime
  from shutil import rmtree
  from unittest import TestCase
  from niftynet.utilities.niftynet_global_config import NiftyNetGlobalConfig
label_desc: Use image node_id 1 for calling the TestIncorrectConfigFileBackedUp obj's underlying member method code with example usage: obj.test_incorrect_config_file_backed_up() without return types