...basically, it says to save two files as extension
/usr/local/etc/cups/printers.conf
/usr/local/etc/cups/ppd/printer_specific.ppd
yes, perhaps you may read .Info of cups is more implicit, however, more or less the files are the same
"To persist across boots, add the following to your backup:
/usr/local/etc/cups/ppd/HP_OfficeJet_G85.ppd [for example]
/usr/local/etc/cups/printers.conf
/usr/local/etc/cups/cupsd.conf (only if you changed it)
/etc/shadow (if you want to save to root password"
You can create an extension of any file on your filesystem, compared to the backup file simply change the format and functionality.