docs: def check_ocrmypdf(input_file, output_file, *args, env=None):
      "Run ocrmypdf and confirmed that a valid file was created"
  
      p, out, err = run_ocrmypdf(input_file, output_file, *args, env=env)
      if p.returncode != 0:
          print('stdout\n======')
          print(out)
          print('stderr\n======')
          print(err)
      #assert p.returncode == 0
      #assert os.path.exists(output_file), "Output file not created"
      #assert os.stat(output_file).st_size > 100, "PDF too small or empty"
      return output_file