That is from a rat.It will get better after a few sheds,but it will never go away.This will scar the pattern.Also the snake may go off food(fear).Unfortunatly I missed a rat one feeding day and this happened to one of my Het.caramel females.She is back eating and has had numerous sheds,but the scars remain.Should not effect the snakes ability to breed,but he/she wont be a "looker".All the best