New baby ball python won't eat frozen/thawed pinky

[Stewart_Reptiles]

So I'm about to go out should I get a frozen hopper or a live hopper?

First thing before even attempting any feeding make sure your setup is optimum for an hatchling follow the link Pit posted to a T, once you do that offer live hopper (as mentioned pinkies are not appropriate for a BP), and do so for 3 to 5 feeding before attempting to switch to F/T.

Right now the priority is for the animal to eat not to be switch, and you will have better results if you attempt to switch a well established animal rather than switching one that is not.