You might be able to shrink it down using sugar (you can on a mammal's organ) to reinsert it. However since it's coming from the vent, it would be best that the snake be kept on a liquid type diet....A/D cat food from vet thinned down and fed w/a tube, so the feces remains watery until healed, otherwise the snake will just push it out again. You could use unwaxed dental floss and stitch it back up to healing, but again, have to be very careful to allow for elimination, or THAT inability could harm the snake.