Pro Sites: check if user is paid or not

So back when pro -sites was supporter, I had this php logic that displayed a link if they were paid, and another if they were not paid current.. I've long since lost this code, and Im trying to find some documentation on this for pro sites!
Cant find any info in the forum, googled, looked for readmes.txts and all sorts. could someone point me to where I can find these shortcodes again?