code: def _check_is_range(self, data_loader, N):
      # check that data_loader produces range(N)
      data = list(iter(data_loader))
      data = [x for batch in data for x in batch]  # flatten the batches
      self.assertEqual(len(data), N)
      self.assertEqual(set(data), set(range(N)))
  
imports: import os
  import pickle
  import sys
  import unittest
  from functools import partial
  import torch
  from iopath.common.file_io import LazyPath
  from detectron2 import model_zoo
  from detectron2.config import get_cfg, instantiate
  from detectron2.data import DatasetCatalog, DatasetFromList, MapDataset, ToIterableDataset, build_batch_data_loader, build_detection_test_loader, build_detection_train_loader
  from detectron2.data.common import AspectRatioGroupedDataset, set_default_dataset_from_list_serialize_method
  from detectron2.data.samplers import InferenceSampler, TrainingSampler
label_desc: Use image node_id 5 for calling the TestDataLoader obj's underlying member method code with example usage: obj._check_is_range(data_loader, N) without return types