Give him time to adjust. He will not eat if stressed. Keep offering food, change water every few days and keep handling to a minimum. Keep him in a low traffic area. Have you provided multiple hides in different temp ranges? Have you set a definite photoperiod, to much light may be stressing him. He will feel more comfortable in the dark. Have you provided UVB, UVB stimulates appetite. You do not sound very experienced, buy books about caring for pythons in captivity.