def setRequired(self,req=1):
        if req: self.setTag('required')
        else:
            try: self.delChild('required')
            except ValueError: return
Was there a significant type change between old and new data?
dataset/ETHPy150Open CouchPotato/CouchPotatoServer/libs/xmpp/protocol.py/DataField.setRequired--crossover with--dataset/ETHPy150Open blaze/blaze/blaze/compute/core.py/type_change