Formats the slot for network packing.

def get_dict(self):
        """ Formats the slot for network packing. """
        data = {'id': self.item_id}
        if self.item_id != constants.INV_ITEMID_EMPTY:
            data['damage'] = self.damage
            data['amount'] = self.amount
            if self.nbt is not None:
                data['enchants'] = self.nbt
        return data