code: def evaluation_step(
      self, batch, batch_idx, dataloader_idx: int = 0, tag: str = "val"
  ):
      pass
  
imports: from abc import ABC, abstractmethod
  from typing import List, Union
  import hydra
  import torch
  from omegaconf import DictConfig, OmegaConf
  from pytorch_lightning import Trainer
  from nemo.collections.asr.metrics.audio import AudioMetricWrapper
  from nemo.core.classes import ModelPT
  from nemo.utils import logging, model_utils
label_desc: Use image node_id 5 for calling the AudioToAudioModel obj's underlying member method code with example usage: obj.evaluation_step(batch, batch_idx, dataloader_idx, tag) without return types