code: def data(self):
      if self._data is None:
          self._data_file = h5py.File(self.split_filename, "r")
          self._data = self._data_file["datasets"]
      return self._data
  
imports: import numpy
  from PIL import Image
  import os
  import io
  import json
  import glob
  import h5py
  from torchmeta.utils.data import Dataset, ClassDataset, CombinationMetaDataset
  from torchmeta.datasets.utils import download_file_from_google_drive
  from torchmeta.datasets.utils import get_asset
label_desc: Use image node_id 4 for calling the TripleMNISTClassDataset obj's underlying member method code with example usage: obj.data() and returns: self