code: def on_validation_batch_end(
      self, trainer, pl_module, outputs, batch, *_
  ):
      _device_check_helper(batch.device, pl_module.device)
  
imports: import pytest
  from lightning.pytorch import Callback, Trainer
  from lightning.pytorch.demos.boring_classes import BoringModel
  from tests_pytorch.helpers.runif import RunIf
label_desc: Use image node_id 4 for calling the BatchHookObserverCallback obj's underlying member method code with example usage: obj.on_validation_batch_end(trainer, pl_module, outputs, batch) without return types