Print Format Export Default

Hello,

I have a custom module, and when I press the print button I get a nice default print format, which I really like, but would like to add some fields from other doctypes, etc. Things that I can do by using Jinja. But most of the work is already done by the default print format, is there anyway I could get the source of that Template, before rendering, to be able to create a new format, editing the bits I need?