code: def test_video_dataset_dataloader__video_reader(self):
      torchvision.set_video_backend("video_reader")
      self._test_video_dataset_dataloader()
  
imports: import contextlib
  import io
  import os
  import shutil
  import tempfile
  import unittest
  from fractions import Fraction
  from typing import List
  from unittest import mock
  import cv2
  import numpy
  import PIL
  import torch
  import torchvision
  from lightly.data import LightlyDataset, NonIncreasingTimestampError
  from lightly.data._video import VideoDataset, _find_non_increasing_timestamps, _make_dataset
label_desc: Use image node_id 16 for calling the TestVideoDataset obj's underlying member method code with example usage: obj.test_video_dataset_dataloader__video_reader() without return types