The hard part is enforcement. The court's enforcement arm is the US Marshal service, but it's under DOJ. Could the court enter an order appointing a (willing) third-party jailer, i.e., the state/county? Who knows, so do it anyway. However long that fucker is jailed before reversal is worth it.
loafstaFederal courts possess inherent authority to independently enforce contempt charges. If DOJ declines to prosecute, the court may appoint an independent special prosecutor to try the case. That said, it would almost certainly reach SCOTUS if the AG was the defendant.