Brought a small dog with me on the plane a few weeks ago- O. K. if the pet container fits under the seat in front of you. Cost me $40 for the animal's fare. Dunno how the current flap affects this carry-on.
When I looked up the restrictions I didn't see any prohibition on snakes. Why should there be if the snake is among those legally sold as pets and is not too large for the carry-on cage?