code: def __getitem__(self, index):
      if index > self.l:
          raise IndexError
      np.random.seed(index)
      return index, np.random.randint(
          0, 255, size=self.size, dtype="u1"
      )
  
imports: import os
  from tempfile import NamedTemporaryFile
  from time import sleep, time
  import os, psutil
  import numpy
  import pytest
  from tqdm import tqdm
  from assertpy import assert_that
  from torch.utils.data import Dataset
  from ffcv.writer import DatasetWriter
  from ffcv.reader import Reader
  from ffcv.fields import BytesField, IntField
  from ffcv.pipeline.compiler import Compiler
  from ffcv import Loader
label_desc: Use image node_id 3 for calling the DummyDataset obj's underlying member method code with example usage: obj.__getitem__(index) and returns: index,  np