code: def test_resume_train(self) -> None:
      self.training_cfg.epoch_num = 2
      self.op.train(
          training_config=self.training_cfg,
          train_dataset=self.train_data,
          resume_checkpoint_path=self.training_cfg.output_dir
          + "/epoch_1",
      )
  
imports: import unittest
  import torchvision
  from pathlib import Path
  from shutil import rmtree
  from torch import nn
  from torch.optim import AdamW
  from torchvision import transforms
  from towhee.operator import NNOperator
  from towhee.trainer.training_config import TrainingConfig
  from towhee.data.dataset.image_datasets import PyTorchImageDataset
label_desc: Use image node_id 5 for calling the TrainerTest obj's underlying member method code with example usage: obj.test_resume_train() without return types