code: def setUpClass(cls):
      dataset_dir = os.path.join(cls.get_base_temp_dir(), "musan")
      cls.samples = _get_mock_dataset(dataset_dir)
  
file_path: audio/test/torchaudio_unittest/prototype/datasets/musan_test.py
imports: import os
  from collections import defaultdict
  from parameterized import parameterized
  from torchaudio.prototype.datasets import Musan
  from torchaudio_unittest.common_utils import get_whitenoise, save_wav, TempDirMixin, TorchaudioTestCase
label_desc: Use image node_id 1 for calling the MusanTest obj's underlying member method code with example usage: obj.setUpClass(cls) without return types