code: def test_barkscale(self):
      sample_rate = 8000
      n_fft = 400
      n_barks = n_fft // 2 + 1
      transform = T.BarkScale(sample_rate=sample_rate, n_barks=n_barks)
      spec = get_spectrogram(
          get_whitenoise(
              sample_rate=sample_rate, duration=0.05, n_channels=2
          ),
          n_fft=n_fft,
          power=1,
      )
      self.assert_grad(transform, [spec])
  
file_path: audio/test/torchaudio_unittest/prototype/transforms/autograd_test_impl.py
imports: from typing import List
  import torch
  import torchaudio.prototype.transforms
  from torch.autograd import gradcheck, gradgradcheck
  from torchaudio_unittest.common_utils import get_spectrogram, get_whitenoise, TestBaseMixin
label_desc: Use image node_id 3 for calling the Autograd obj's underlying member method code with example usage: obj.test_barkscale() without return types