code: def setUpClass(cls):
      NiftyNetGlobalConfigTestBase.setUpClass()
  
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 TestGlobalConfigSingleton obj's underlying member method code with example usage: obj.setUpClass(cls) without return types