code: def main(cfg):
      trainer = pl.Trainer(**cfg.trainer)
      exp_manager(trainer, cfg.get("exp_manager", None))
      model = HifiGanModel(cfg=cfg.model, trainer=trainer)
      trainer.fit(model)
  
imports: import pytorch_lightning
  from nemo.collections.tts.models import HifiGanModel
  from nemo.core.config import hydra_runner
  from nemo.utils.exp_manager import exp_manager
label_desc: Use image node_id 1 for calling a global function with example usage: main(cfg) without return types