code: def on_validation_epoch_end(
      self,
      trainer: "pl.Trainer",
      pl_module: "pl.LightningModule",
  ):
      self.val_logger.write_epoch(trainer.current_epoch)
  
imports: import logging
  import math
  import os
  import sys
  import time
  from typing import Any, Dict, Optional
  import torch
  from torch_geometric.graphgym import register
  from torch_geometric.graphgym.config import cfg
  from torch_geometric.graphgym.imports import Callback, pl
  from torch_geometric.graphgym.utils.device import get_current_gpu_usage
  from torch_geometric.graphgym.utils.io import dict_to_json, dict_to_tb
label_desc: Use image node_id 14 for calling the LoggerCallback obj's underlying member method code with example usage: obj.on_validation_epoch_end(trainer, pl_module) without return types