code: def _get_model(self):
      return (
          hifigan_vocoder(**self._get_model_config())
          .to(device=self.device, dtype=self.dtype)
          .eval()
      )
  
imports: import math
  import torch
  from parameterized import parameterized
  from torchaudio.prototype.models import hifigan_vocoder, hifigan_vocoder_v1, hifigan_vocoder_v2, hifigan_vocoder_v3
  from torchaudio.prototype.pipelines import HIFIGAN_VOCODER_V3_LJSPEECH
  from torchaudio_unittest.common_utils import TestBaseMixin, torch_script
  from .original.env import AttrDict
  from .original.meldataset import mel_spectrogram
  from .original.models import Generator
label_desc: Use image node_id 3 for calling the HiFiGANTestImpl obj's underlying member method code with example usage: obj._get_model() and returns: hifigan_vocoder