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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _process(compressor, input_filename, output_filename):
 """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. """

    compressor(input_filename, output_filename)
    result_size = os.path.getsize(output_filename)

    return _CompressorResult(result_size, output_filename, compressor.__name__)