I find maybe one in ten or one in twenty babies are genuinely nippy. Most of the snakes I've had shipped to my house have arrived in a bad mood, especially if they were shipped in cold weather. But most of them also calmed down after a couple weeks. The two genuine biters I had (which includes Mr. Nibbles, my very first ball python) both calmed down after their second winter, and are only a little grumpy right around shed time. So, worst case scenario, the baby will bite for a year, and then calm down. But there's at least a 50/50 chance it'll stop biting after it's settled in and had a couple meals.
Anyway: point is, it's not really the breeder's fault. Snakes have a limited number of ways of interacting with the world, and some baby ball pythons are just defensive. If the breeder is willing to give you your money back, minus the shipping, that's great. If not, you should be able to get most of your money (probably minus the shipping) by selling her on kingsnake. Somebody will almost certainly want a really pretty female bee.
(Just wondering: has she eaten for you?)
When you do find a buyer, I recommend using Ship Your Reptiles.com, and following their directions carefully to make sure you ship her correctly and legally.