Assuming all the husbandry issues are good, it may just be because it's winter. Ball pythons are known to be picky eaters. I'm going through it right now. Last year when I got mine (in January) she had just started eating. And this year as soon as the weather changed outside, she quit eating.
1) temps?
2) humidity?
3) hides?
4) any clicking or poping sounds?
5) When you say "blue" are you talking about pre-shed IE in blue?
6) Did you move her cage? different room? Did you rearrange the cage?
7) Changes in behavior or patterns? resting head on hides?
Here is the best suggestions I have.
-If Zatarra is in blue it's not uncommon for ball pythons to skip a meal before shed.
-Seasonal (hibernation) Is she/he burrowing?
It's not uncommon for them to go a couple of months without eating. When breading for example.
Check out- http://www.kingsnake.com/ballpythonguide/
Quote Originally Posted by http://www.kingsnake.com/ballpythonguide/#BREEDING
The breeding process is a year long cycle. During the spring, summer, and early fall, my snakes are housed separately, kept at optimal temperatures, and fed every two or three weeks. In about October or November, I stop feeding the snakes and leave them at regular temperatures. After a few weeks without food, I move my two males and three female adults together into a 60 Gallon aquarium (30x18x18 inches). The tank has three hide boxes, one of which acts as the water bowl. I provide regular temps in the high 80's during the day and until about 2:00am. At 2:00am, I turn off the lights and let the temperature drop into the low 70's or even high 60's. The light comes back on at 11:00am and warms things back up. Some breeders have had success offering 12 hours of light and 12 of dark, but mine seem to do OK. I continue to offer food to the females every three or four weeks, but I expect that they will choose not to eat. Some breeders have also suggested providing more humidity during the mating season, but again mine seem to do fine without worrying about that factor.