code: def test_dither_noise(self):
      path = get_asset_path("steam-train-whistle-daniel_simon.wav")
      data, _ = load_wav(path)
      result = F.dither(data, noise_shaping=True)
      self.assert_sox_effect(
          result, path, ["dither", "-s"], atol=1.5e-4
      )
  
imports: import torch
  import torchaudio.functional
  from torchaudio_unittest.common_utils import get_asset_path, get_whitenoise, load_wav, save_wav, skipIfNoExec, skipIfNoSox, sox_utils, TempDirMixin, TorchaudioTestCase
label_desc: Use image node_id 6 for calling the TestFunctionalFiltering obj's underlying member method code with example usage: obj.test_dither_noise() without return types