Ok first off you can't run multiple appliances off of one thermostat. With your setup I would have the thermostat controlling just the UTH. The thermostat probe needs to go outside the tank between the UTH and the bottom of the tank. Use an IR thermometer, or one with a probe, to measure the surface temperature on the glass, and set the thermostat so the glass surface temperature is about 90*F. You may have to thin the aspen under the hot hide a bit so your ball python has access to it.

Second, ditch one of the lights. Ball pythons primarily live underground in termite mounds and hunt at night, they don't need bright light. Put a heat lamp in the other fixture if you need to raise the ambient temperature.

Cover the top of the tank, leaving space for the heat lamp, with something like foil or Glad Press N Seal to help keep humidity in the tank.

If you have problems keeping the humidity up you can switch from aspen to cypress mulch during the winter. Cypress retains and releases more moisture without getting moldy than aspen does.