code: def test_HifiGanModel_export_to_onnx(self, hifigan_model):
      model = hifigan_model.cuda()
      assert hifigan_model.generator is not None
      with tempfile.TemporaryDirectory() as tmpdir:
          filename = os.path.join(tmpdir, "hfg.onnx")
          model.export(output=filename, verbose=True, check_trace=True)
  
file_path: NeMo/tests/collections/tts/test_tts_exportables.py
imports: import os
  import tempfile
  import pytest
  import torch
  from omegaconf import OmegaConf
  from nemo.collections.tts.models import FastPitchModel, HifiGanModel, RadTTSModel
  from nemo.utils.app_state import AppState
label_desc: Use image node_id 2 for calling the TestExportable obj's underlying member method code with example usage: obj.test_HifiGanModel_export_to_onnx(hifigan_model) without return types