I'm trying to use the ROM bootloader on the SAMG55 as described in AT09002. The application note describes using a tool 'hex2fw.py'. Where can I get that and the config files it uses?

I found this thread - https://community.atmel.com/forum/entering-bootloader-atmel-samg55-xplained-pro - which has a modified version of the script, but no config files that it needs.