Looking for a script to convert a project from twos to ones

[Lukas]

I'm hoping someone already made something like this.

I have a project on 12.5 fps (animated on twos), and I'd like to convert it to 25 fps and stretch the project length by 100% and have all keyframes set to interval:2 (so the character animation is still on twos) except for the camera keyframes (so they'd be on ones so I'd have a fluid camera movement).

Any help is appreciated! (I'm probably going to have to do this by hand...but you never know!)