Oh yeah, add an under the tank heater or human heating pad for the warm side - that should help the temps over there. If your cool side is still too cool add another light or just use one higher wattage light. Use infrared lights so that you can leave them on 24/7 w/o disturbing your snake. Your under the tank heater should be on 24/7 also. Be sure you measure your temps with a good quality thermometer - stick ons are usually regarded as crap. i recommend a good digital probe thermometer. Be sure you humidity is correct: 50-60% minimum and up to at least 70% during shed. What about the rest of your setup: hides, water bowl, substrate,etc? You probably should post this in the Ball Python forum as I think this is more for cage building, etc. You'll probably get more advice there. 
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0.1 Tigergenesis "Kelly"
1.0 Ball Python "Aragorn"
1.0 Kenyan Sand Boa "Gimli"
0.1 Australian Cattle Dog/Pointer "Kira"