Any core/real reference to *assret* as alias to *assert*

I see it mentioned in a few places, all appear to stem from same issue filed against python core:

http://ift.tt/1Hq63B7 http://ift.tt/1RtL22l (unsafe kwarg) http://ift.tt/1Hq63B9

Is there a precedent for this spelling?

It appears intentional, but there's nothing else in the docs pointing to such use.