code: def __len__(self):
      return len(self.labels)
  
imports: import argparse
  import datetime
  import os
  import sys
  import time
  import dgl
  import torch
  from dgl.data.utils import load_graphs, save_graphs
  from dgl.dataloading import GraphDataLoader
  from ogb.linkproppred import DglLinkPropPredDataset, Evaluator
  from torch.nn import BCEWithLogitsLoss
  from torch.utils.data import Dataset
  from tqdm import tqdm
  from models import *
  from utils import *
label_desc: Use image node_id 2 for calling the SEALOGBLDataset obj's underlying member method code with example usage: obj.__len__() and returns: len