code: def test_step(self, batch, batch_idx):
      loss = self.forward(batch)
      return {"test_loss": loss}
  
imports: import torch
  import torch.nn
  import torch.nn.functional
  from torch.utils.data import DataLoader
  from torchmetrics import Accuracy
  from ray import train
  from ray.train.lightning._lightning_utils import import_lightning
label_desc: Use image node_id 5 for calling the LinearModule obj's underlying member method code with example usage: obj.test_step(batch, batch_idx) and returns: dict