Request Tool Ren'Py Saving small images as multigame persistent data

[deskrabbit]

Hi. Does anyone know if there is a way to save binary image data as a multigame persistent variable? It's a weird request I know. I'm creating a serials of small self contained games but want to share achievment badges accross them. Like, icon sized images. So not a lot of data. I see the im.Data class and some other topics online that hint at saving image data and writing to a new file but nothing so specific.

Thanks in advance.