code: def on_train_end(self, trainer, pl_module):
      for lightning_loss, mmf_loss in zip(
          self.lightning_losses, self.mmf_losses
      ):
          self.assertEqual(lightning_loss, mmf_loss)
  
file_path: mmf/tests/trainers/lightning/test_loss.py
imports: import unittest
  from unittest.mock import MagicMock, patch
  from mmf.common.report import Report
  from pytorch_lightning.callbacks.base import Callback
  from tests.trainers.test_utils import get_config_with_defaults, get_lightning_trainer, get_mmf_trainer
label_desc: Use image node_id 4 for calling the TestLightningTrainerLoss obj's underlying member method code with example usage: obj.on_train_end(trainer, pl_module) without return types