Assuming you put the cal in /home/pi/flashfiles/tunes/thisismytune.bin
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cd /home/pi/VW_FLASHVW_Flashpython3 checksumsimoschecksumsimos18.py -i /home/pi/flashfiles/tunes/thisismytune.bin -o /home/pi/flashfiles/tunes/thisismytune.bin.checksummed --block 5
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