1. I do not recommend a heat/basking bulb. Ball Python's need a good amount of humidity (55-70%) and the water vapor (humidity is water vapor) will essentially rise and be "baked" out of the enclosure. Therefore I recommend getting an under Tank Heater (A.k.a UTH/Heat mat). You will also want something called a thermostat. It controls the temperature of your hest source (I.E UTH, Heat lamp) to prevent over heating and under heating. I can link one if you'd like. Other than that it sounds like your enclosure should be fine. Things you will want to invest in to complete your setup
1. Thermostat
2. UTH
3. Thermometer/Hygrometer combo. (Look up Acurite Home Comfort Monitor)
And then you'll want to cover 3/4 of the mesh screen with something to keep in humidity. Hope this helps!
Erik