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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 rotate_even_pages_180(input_filename: str, output_filename: str) -> str: """ Rotates even-numbered pages 180 degrees. Returns the output filename. """

    log.info("Rotating even-numbered pages 180 degrees for long-edge "
             "duplex printing")
    log.debug("... {!r} -> {!r}", input_filename, output_filename)
    require(PDFTK, HELP_MISSING_PDFTK)
    args = [
        PDFTK,
        "A=" + input_filename,  # give it handle 'A'
        # handles are one or more UPPER CASE letters
        "shuffle",
        "Aoddnorth",  # for 'A', keep odd pages as they are
        "Aevensouth",  # for 'A', rotate even pages 180 degrees
        "output", output_filename,
    ]
    run(args)
    return output_filename