We keep Blood Pythons at a 50%-60% humidity, measured by a hygrometer. They’re inexpensive, often less than $20, and will remove all the guesswork. The humidity in the room might not be the same as the one inside the tub, so measure both to be safe.
If you need to raise the humidity in your reptile room, buy an evaporative humidifier. Do not by an ultrasonic one as they leave a messy white dust everywhere.
When one of our Blood Pythons is in shed, we spray the animal with water, put a layer of paper on top, then spray the paper. All sheds come out perfect.