code: def subtype(self):
      if self._params["ext"] == "ogg":
          return "VORBIS"
      return dtype2subtype(self._params["dtype"])
  
imports: import os
  import tarfile
  from functools import partial
  from unittest.mock import patch
  import torch
  from parameterized import parameterized
  from torchaudio._backend.utils import get_load_func
  from torchaudio._internal import module_utils
  from torchaudio_unittest.common_utils import get_wav_data, load_wav, normalize_wav, PytorchTestCase, save_wav, skipIfNoModule, TempDirMixin
  from .common import dtype2subtype, parameterize, skipIfFormatNotSupported
label_desc: Use image node_id 4 for calling the SoundFileMock obj's underlying member method code with example usage: obj.subtype() and returns: dtype2subtype, str