code: def testMp3TimeShift(self):
      # test mp3s are loaded with no time shift (lost frames)
      filename_mp3 = join(mp3_dir, "impulses_1second_44100.mp3")
      filename_wav = join(wav_dir, "impulses_1second_44100.wav")
      mp3 = self.load(filename_mp3, "mix", 44100)
      wav = self.load(filename_wav, "mix", 44100)
  
      # find time shift between impulse positions
      impulses_mp3 = [x for x in range(len(mp3)) if mp3[x] > 0.9]
      impulses_wav = [x for x in range(len(wav)) if wav[x] > 0.9]
  
      shift = impulses_mp3[0] - impulses_wav[0]
      # FIXME:
      # For this particular audio files in essentia 2.1_beta2 with an older libav version
      # the expected shift was 1105 samples, however now there is no shift
      # Nevertheless time shift can be observed on other examples but we still do not have such tests
  
      # self.assertEqual(abs(shift), 1105)
      self.assertEqual(abs(shift), 0)
  
imports: from essentia_test import *
  from numpy import fabs
label_desc: Use image node_id 13 for calling the TestMonoLoader obj's underlying member method code with example usage: obj.testMp3TimeShift() without return types