Modding Help [Fixed}Need help on a flamethrower upgrade mod

Hi! I'm new to the forums so sorry if I don't format something correctly or whatever. Long story short, I'm making a flamethrower mod that will be a craftable upgrade to the flamethrower, and will be upgrade-able at the weapon upgrade anvil from the vanilla game. Only thing is that it won't show up in the upgrade anvil, and my game crashes if i try to remove the upgrade part from the script and make the upgraded version a separate item. Anyone know what I'm doing wrong? Thanks id advance!

 

Alright i figured it out, turns out i had just forgotten to delete a single comma. I figured out what was wrong when running it through a JSON checker. Whoops!