code: def test_audio(self):
      audio, sampling_rate = AudioLoader.load_audio(
          self.sample_wav_file
      )
  
      flow = naf.Sequential(
          [
              naa.NoiseAug(),
              naa.PitchAug(
                  sampling_rate=sampling_rate, factor=(0.2, 1.5)
              ),
              naa.ShiftAug(sampling_rate=sampling_rate, duration=2),
              naa.SpeedAug(factor=(1.5, 3)),
          ]
      )
  
      augmented_audio = flow.augment(audio)
  
      self.assertFalse(np.array_equal(audio, augmented_audio))
      self.assertTrue(len(audio), len(augmented_audio))
  
file_path: nlpaug/test/flow/test_sequential.py
imports: import unittest
  import os
  import numpy
  from dotenv import load_dotenv
  import nlpaug.augmenter.char
  import nlpaug.augmenter.word
  import nlpaug.augmenter.spectrogram
  import nlpaug.augmenter.audio
  import nlpaug.flow
  from nlpaug.util import Action, AudioLoader
label_desc: Use image node_id 6 for calling the TestSequential obj's underlying member method code with example usage: obj.test_audio() without return types