docstr: Test if audio frames are returned with sec unit.
docstr_tok: ["Test","if","audio","frames","are","returned","with","sec","unit","."]
code: def test_audio_present_sec(
      self, test_video, backend, start_offset, end_offset
  ):
      """Test if audio frames are returned with sec unit."""
      full_path = os.path.join(VIDEO_DIR, test_video)
      container = av.open(full_path)
      if container.streams.audio:
          set_video_backend(backend)
          _, audio, _ = io.read_video(
              full_path, start_offset, end_offset, pts_unit="sec"
          )
          assert all([dimension > 0 for dimension in audio.shape[:2]])
  
imports: import collections
  import math
  import os
  from fractions import Fraction
  import numpy
  import pytest
  import torch
  import torchvision.io
  from common_utils import assert_equal
  from numpy.random import randint
  from pytest import approx
  from torchvision import set_video_backend
  from torchvision.io import _HAS_VIDEO_OPT
label_desc: Use image node_id 25 for calling the TestVideoReader obj's underlying member method code with example usage: obj.test_audio_present_sec(test_video, backend, start_offset, end_offset) without return types