How to use the pydal.helpers.methods.xorify function in pydal

item = ndb.Key.from_old_key(filters._FilterNode__value).get()
            items = [item] if item else []
        else:
            items = tableobj.query(filters, default_options=qo)

        if count_only:
            items = [len(items) if isinstance(items,list) else items.count()]
        elif not isinstance(items,list):
            if args_get('left', None):
                raise SyntaxError('Set: no left join in appengine')
            if args_get('groupby', None):
                raise SyntaxError('Set: no groupby in appengine')
            orderby = args_get('orderby', False)
            if orderby:
                if isinstance(orderby, (list, tuple)):
                    orderby = xorify(orderby)
                if isinstance(orderby,Expression):
                    orderby = self.expand(orderby)
                orders = orderby.split(', ')
                tbl = tableobj
                for order in orders:
                    order = str(order)
                    desc = order[:1] == '-'
                    name = order[1 if desc else 0:].split('.')[-1]
                    if name == 'id':
                        o = -tbl._key if desc else tbl._key
                    else:
                        o = -getattr(tbl, name) if desc else getattr(tbl, name)
                    items = items.order(o)

            if args_get('limitby', None):
                (lmin, lmax) = attributes['limitby']

item = ndb.Key.from_old_key(getattr(filters, "_FilterNode__value")).get()
            items = [item] if item else []
        else:
            items = tableobj.query(filters, default_options=qo)

        if count_only:
            items = [len(items) if isinstance(items, list) else items.count()]
        elif not isinstance(items, list):
            if args_get("left", None):
                raise SyntaxError("Set: no left join in appengine")
            if args_get("groupby", None):
                raise SyntaxError("Set: no groupby in appengine")
            orderby = args_get("orderby", False)
            if orderby:
                if isinstance(orderby, (list, tuple)):
                    orderby = xorify(orderby)
                if isinstance(orderby, Expression):
                    orderby = self.expand(orderby)
                orders = orderby.split(", ")
                tbl = tableobj
                for order in orders:
                    order = str(order)
                    desc = order.startswith("-")
                    name = order[1 if desc else 0 :].split(".")[-1]
                    if name == "id":
                        o = -tbl._key if desc else tbl._key
                    else:
                        o = -getattr(tbl, name) if desc else getattr(tbl, name)
                    items = items.order(o)

            if args_get("limitby", None):
                (lmin, lmax) = attributes["limitby"]

limitby = attributes.get('limitby', False)
        # distinct = attributes.get('distinct', False)
        if 'for_update' in attributes:
            self.db.logger.warning('mongodb does not support for_update')
        for key in set(attributes.keys())-set(('limitby', 'orderby',
                                               'for_update')):
            if attributes[key] is not None:
                self.db.logger.warning(
                    'select attribute not implemented: %s' % key)
        if limitby:
            limitby_skip, limitby_limit = limitby[0], int(limitby[1]) - 1
        else:
            limitby_skip = limitby_limit = 0
        if orderby:
            if isinstance(orderby, (list, tuple)):
                orderby = xorify(orderby)
            # !!!! need to add 'random'
            for f in self.expand(orderby).split(','):
                if f.startswith('-'):
                    mongosort_list.append((f[1:], -1))
                else:
                    mongosort_list.append((f, 1))
        for item in fields:
            if isinstance(item, SQLALL):
                new_fields += item._table
            else:
                new_fields.append(item)
        fields = new_fields
        if isinstance(query, Query):
            tablename = self.get_table(query)
        elif len(fields) != 0:
            if isinstance(fields[0], Expression):

item = ndb.Key.from_old_key(filters._FilterNode__value).get()
            items = [item] if item else []
        else:
            items = tableobj.query(filters, default_options=qo)

        if count_only:
            items = [len(items) if isinstance(items,list) else items.count()]
        elif not isinstance(items,list):
            if args_get('left', None):
                raise SyntaxError('Set: no left join in appengine')
            if args_get('groupby', None):
                raise SyntaxError('Set: no groupby in appengine')
            orderby = args_get('orderby', False)
            if orderby:
                if isinstance(orderby, (list, tuple)):
                    orderby = xorify(orderby)
                if isinstance(orderby,Expression):
                    orderby = self.expand(orderby)
                orders = orderby.split(', ')
                tbl = tableobj
                for order in orders:
                    order = str(order)
                    desc = order[:1] == '-'
                    name = order[1 if desc else 0:].split('.')[-1]
                    if name == 'id':
                        o = -tbl._key if desc else tbl._key
                    else:
                        o = -getattr(tbl, name) if desc else getattr(tbl, name)
                    items = items.order(o)

            if args_get('limitby', None):
                (lmin, lmax) = attributes['limitby']

)
                )
            tokens += [self.dialect.left_join(t, query_env) for t in join_on]
            sql_t = " ".join(tokens)
        else:
            sql_t = ", ".join(table_alias(t) for t in query_tables)
        #: expand query if needed
        if query:
            query = self.expand(query, query_env=query_env)
        if having:
            having = self.expand(having, query_env=query_env)
        #: groupby
        sql_grp = groupby
        if groupby:
            if isinstance(groupby, (list, tuple)):
                groupby = xorify(groupby)
            sql_grp = self.expand(groupby, query_env=query_env)
        #: orderby
        sql_ord = False
        if orderby:
            if isinstance(orderby, (list, tuple)):
                orderby = xorify(orderby)
            if str(orderby) == "":
                sql_ord = self.dialect.random
            else:
                sql_ord = self.expand(orderby, query_env=query_env)
        #: set default orderby if missing
        if (
            limitby
            and not groupby
            and query_tables
            and orderby_on_limitby

#: expand query if needed
        if query:
            query = self.expand(query, query_env=query_env)
        if having:
            having = self.expand(having, query_env=query_env)
        #: groupby
        sql_grp = groupby
        if groupby:
            if isinstance(groupby, (list, tuple)):
                groupby = xorify(groupby)
            sql_grp = self.expand(groupby, query_env=query_env)
        #: orderby
        sql_ord = False
        if orderby:
            if isinstance(orderby, (list, tuple)):
                orderby = xorify(orderby)
            if str(orderby) == "":
                sql_ord = self.dialect.random
            else:
                sql_ord = self.expand(orderby, query_env=query_env)
        #: set default orderby if missing
        if (
            limitby
            and not groupby
            and query_tables
            and orderby_on_limitby
            and not orderby
        ):
            sql_ord = ", ".join(
                [
                    tablemap[t][x].sqlsafe
                    for t in query_tables