Making sure the cool side doesent get too cold.

I really want a ball python, and have done my research. I've taken care of corns before, so im not totally new to this, but my basic concern here is that I would use a tub, and an UTH for the heat. But my room is in the mid 60's, and I can't raise the temp. I just want to make sure that by using a UTH for the hot side, it will also make sure the cool side doesent get too cold. Thanks in advance.

You could use two UTHs or get a space heater for the room.

Unfortunately there aren't many options for upping the ambient temperature in stand alone tubs. Most people who use tubs use them in a rack system which helps insulate them pretty well.

If all else fails, you could use a (dare I say it) tank with a ceramic heat emmitter + UTH.

You could use a radiant heat panel. Big Apple Herp sells them.