1. 50* is nearing refrigeration temps and you're never going to achieve a proper climate for an African python species in those conditions. Don't assume it's 50*, measure the temperature.
2. Put snake in different room that is warmer.
3. Heatpad will do zero for those ambient temps.
Get back to us with the room temps and maybe we can offer a solution. If the room is indeed that cold you'll need to heat the room. Even insulating the sides and top of the tank and using a CHE you'll run into issues with the room temp that cold.