code: def hifigan_model():
      model = HifiGanModel.from_pretrained(model_name="tts_en_hifigan")
      return model
  
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 a global function with example usage: hifigan_model() and returns: model