code: def test_frontend_output_size():
      frontend = DefaultFrontend(fs="16k", n_mels=40)
      assert frontend.output_size() == 40
  
imports: import pytest
  import torch
  from espnet2.asr.frontend.default import DefaultFrontend
label_desc: Use image node_id 2 for calling a global function with example usage: test_frontend_output_size() without return types