class_docstr: Test the correctness of `sox_io_backend.load` for various formats
docstr: `sox_io_backend.load` can load opus file correctly.
docstr_tok: ["`","sox_io_backend.load","`","can","load","opus","file","correctly","."]
code: def test_opus(self, bitrate, num_channels, compression_level):
      """`sox_io_backend.load` can load opus file correctly."""
      ops_path = get_asset_path(
          "io", f"{bitrate}_{compression_level}_{num_channels}ch.opus"
      )
      wav_path = self.get_temp_path(
          f"{bitrate}_{compression_level}_{num_channels}ch.opus.wav"
      )
      sox_utils.convert_audio_file(ops_path, wav_path)
  
      expected, sample_rate = load_wav(wav_path)
      found, sr = sox_io_backend.load(ops_path)
  
      assert sample_rate == sr
      self.assertEqual(expected, found)
  
imports: import itertools
  import torch
  from parameterized import parameterized
  from torchaudio.backend import sox_io_backend
  from torchaudio_unittest.common_utils import get_asset_path, get_wav_data, load_wav, nested_params, PytorchTestCase, save_wav, skipIfNoExec, skipIfNoSox, skipIfNoSoxDecoder, sox_utils, TempDirMixin
  from .common import name_func
label_desc: Use image node_id 9 for calling the TestLoad obj's underlying member method code with example usage: obj.test_opus(bitrate, num_channels, compression_level) without return types