code: def setUpClass(cls):
      if not os.path.exists(LOG_ROOT):
          os.mkdir(LOG_ROOT)
  
      if not os.path.exists(SAVE_ROOT):
          os.mkdir(SAVE_ROOT)
  
      cls.weights_file = os.path.join(SAVE_ROOT, "weights.h5")
      cls.params_file = os.path.join(SAVE_ROOT, "params.json")
      cls.preprocessor_file = os.path.join(
          SAVE_ROOT, "preprocessor.pickle"
      )
  
file_path: anago/tests/test_trainer.py
imports: import os
  import unittest
  from anago.utils import load_data_and_labels
  from anago.models import BiLSTMCRF, save_model
  from anago.preprocessing import IndexTransformer
  from anago.trainer import Trainer
label_desc: Use image node_id 1 for calling the TestTrainer obj's underlying member method code with example usage: obj.setUpClass(cls) without return types