code: def _process(compressor, input_filename, output_filename):
      
      compressor(input_filename, output_filename)
      result_size = os.path.getsize(output_filename)
  
      return _CompressorResult(result_size, output_filename, compressor.__name__)
docs: Helper function to compress an image.
  
      Returns:
        _CompressorResult named tuple, with the resulting size, the name of the
        output file and the name of the compressor.