It looks like stuck skin from a previous shed. You may need to up the humidity. there are many threads on this site on how to up the humidity just do a general search for that topic and you should have no problem finding tips as to how to up the humidity. Also a soak in lukewarm water for a about 5-10 minutes may help him remove some of the skin that is stuck. (there is also a wealth of info on the site about stuck sheds) also looks like he may have retained an eye cap,(i cant be certain from the picture though) the soak has always worked for me and mine are have always been able to remove it on their own. Good luck with everything and welcome to ball pythons.