code: def on_train_batch_end(self, outputs, batch, batch_idx):
      self.log(
          "forward_backward_time",
          time.time() - self.st,
          prog_bar=True,
          on_step=True,
          on_epoch=False,
      )
  
imports: import argparse
  import glob
  import math
  import os
  import time
  import dgl
  import torch
  import torch.nn
  import torch.nn.functional
  from ladies_sampler import LadiesSampler, normalized_edata, PoissonLadiesSampler
  from load_graph import load_dataset
  from model import SAGE
  from pytorch_lightning import LightningDataModule, LightningModule, Trainer
  from pytorch_lightning.callbacks import Callback, EarlyStopping, ModelCheckpoint
  from pytorch_lightning.loggers import TensorBoardLogger
  from torchmetrics.classification import MulticlassF1Score, MultilabelF1Score
label_desc: Use image node_id 5 for calling the SAGELightning obj's underlying member method code with example usage: obj.on_train_batch_end(outputs, batch, batch_idx) without return types