def prepared(self):
        if self.order_by:
            norm_order_by = []
            for item in self.order_by:
                if isinstance(item, Field):
                    prefix = '-' if item._ordering == 'DESC' else ''
                    item = prefix + item.name
                field = self.fields[item.lstrip('-')]
                if item.startswith('-'):
                    norm_order_by.append(field.desc())
                else:
                    norm_order_by.append(field.asc())
            self.order_by = norm_order_by
dataset/ETHPy150Open coleifer/peewee/peewee.py/ModelOptions.prepared/original