class_docstr: GraphDataset for torch DataLoader
class_docstr_tok: ["GraphDataset","for","torch","DataLoader"]
code: def __getitem__(self, index):
      return (self.graph_list[index], self.tensor[index])
  
imports: import os.path
  from copy import deepcopy
  import dgl
  import torch
  from dgl import add_self_loop, DGLGraph, NID
  from dgl.dataloading.negative_sampler import Uniform
  from torch.utils.data import DataLoader, Dataset
  from tqdm import tqdm
  from utils import drnl_node_labeling
label_desc: Use image node_id 3 for calling the GraphDataSet obj's underlying member method code with example usage: obj.__getitem__(index) and returns: self,  self