code: def test_average_nbest_models_0epoch_reporter(output_dir, nbest):
      # Repeat twice to check the case of existing files.
      for _ in range(2):
          average_nbest_models(
              reporter=Reporter(),
              output_dir=output_dir,
              best_model_criterion=[("valid", "acc", "max")],
              nbest=nbest,
          )
  
imports: import pytest
  import torch
  from espnet2.main_funcs.average_nbest_models import average_nbest_models
  from espnet2.train.reporter import Reporter
label_desc: Use image node_id 4 for calling a global function with example usage: test_average_nbest_models_0epoch_reporter(output_dir, nbest) without return types