code: def __getitem__(self, idx):
      if torch.is_tensor(idx):
          idx = idx.tolist()
  
      return self.x[idx, ...], self.y[idx, ...]
  
imports: import os
  import ssl
  import dgl
  import numpy
  import torch
  from six.moves import urllib
  from torch.utils.data import DataLoader, Dataset
label_desc: Use image node_id 3 for calling the SnapShotDataset obj's underlying member method code with example usage: obj.__getitem__(idx) and returns: self,  self