just be patient, he will eat when hes ready. just keep offering and he'll eat when he's ready. Have you had him the whole 10 years? if you are really worried you can have a vet take a look but i really dont think that is necessary at this point, this is what they do.
A room full of empty racks and thermostats that have been unplugged.
If your husbandry is correct, attempt to feed every 5-7 days as usual and be patient. Ball pythons are a pain in all our bums...they are notorious for boycotting food.