code: def validation_step(self, batch, batch_idx):
      return self.eval_step(batch, batch_idx, "val")
  
imports: from typing import Optional, Tuple
  import hydra
  import torch
  import torch.nn
  from omegaconf import DictConfig
  from target_compression_module import TargetRateCompressionModule
  from torch import Tensor
  from neuralcompression import HyperpriorOutput
  from neuralcompression.loss_fn import DiscriminatorLoss, DistortionLoss, GeneratorLoss, TargetRateConfig
  from neuralcompression.models import HyperpriorAutoencoderBase
label_desc: Use image node_id 9 for calling the GANCompressionModule obj's underlying member method code with example usage: obj.validation_step(batch, batch_idx) and returns: self