True length of "record" giant pythons.

[Pirarucu]

I would say that it is possible, though extremely rare, for a large snake to exceed 25 feet. Titanoboa. There you go, snakes have been bigger in the past, so it's possible. We have no proven record of a retic or what have you growing to that size, but absence of proof is not proof of absence.
I saw a picture a few months back of the severed head of a retic killed in Indonesia. Judging by the picture, it looked like the Sulawesi locality, which is known to get larger than average. Looking at the size of the eyes in comparison to the size of the overall head... That was no small retic. Can't be sure how big it was, but it was massive, no doubt about it.