code: def order(cls, query, field, s):
          
          if s == 'asc':
              query = query.order_by(asc(field))
          elif s == 'desc':
              query = query.order_by(desc(field))
          return query
docs: Modify query as so to order the results.
  
          :param query: Query object.
          :param str s: Orderinig: ``asc`` or ``desc``.
          :returs: Query object.