Wow a 40 gallon is wayyyy to big for almost any ball python except a gigantic female breeder. I would really get a smaller enclosure like a rubber maid container or a sterilite container and use a dimmer switch to control the UTH.

NEVER EVER use a UTH without something to control it, some of them only get 120 degrees, which is still to high, but most will get to 150+ degrees without you even realizing it. You don't have to spend $80, but at least go to Lowes or Home Depot and get a lamp dimmer switch for around $10. I really wouldn't worry about it being too humid in a 40 gallon, it's going to be almost impossible for you to keep it at the recommended levels (50-70%) in that size of a tank.

I would really, really invest in a small plastic container, a Dimmer Switch, some paper towels or newspaper and a water bowl with a small hide, this is going to be the best enclosure for your baby.

If shes warm, it is going to be over 95-100 degrees, keep in mind your body temp is 98.6, so if the UTH is hot or the snake is hot to you, the temperature is way too high.