code: def test_coverage(self):
      aug = naa.CropAug(sampling_rate=self.sampling_rate, coverage=0.1)
      augmented_data = aug.augment(self.audio)
      augmented_audio = augmented_data[0]
  
      audio_size = len(self.audio)
      augmented_size = len(augmented_audio)
      expected_crop_size = (
          len(self.audio) * (aug.zone[1] - aug.zone[0]) * 0.1
      )
  
      self.assertTrue(
          -1 <= audio_size - augmented_size - expected_crop_size <= 1
      )
  
file_path: nlpaug/test/augmenter/audio/test_crop.py
imports: import unittest
  import os
  import numpy
  from dotenv import load_dotenv
  import nlpaug.augmenter.audio
  from nlpaug.util import AudioLoader
label_desc: Use image node_id 4 for calling the TestCrop obj's underlying member method code with example usage: obj.test_coverage() without return types