Photoshop: Add Paintshop Pro File Support

I'd really appreciate it if you added support for Paintshop Pro files. I used to work a lot with PSP, and it's extremely annoying that I can't access all my old files on Photoshop (whereas PSP has an option of saving files as psd). I've looked online, but it seems the only solution is to open the files on Paintshop and save them as psd, which is time-consuming and not always possible.