code: def __init__(self, path, npz_file):
      if not os.path.exists(path + "/" + npz_file):
          if not os.path.exists(path):
              os.mkdir(path)
          download_file(npz_file)
      zipfile = np.load(path + "/" + npz_file)
      self.x = zipfile["x"]
      self.y = zipfile["y"]
  
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 1 to create a new SnapShotDataset object from inherited base classes: Dataset with example: obj = SnapShotDataset(path, npz_file)