This commit fixes the following warning by using the mappings() accessor:
sqlalchemy.exc.RemovedIn20Warning: Using non-integer/slice indices on
Row is deprecated and will be removed in version 2.0; please use
row._mapping[<key>], or the mappings() accessor on the Result object.
(Background on SQLAlchemy 2.0 at: https://sqlalche.me/e/b8d9)
This commit fixes the following warning by using the
mappings()
accessor:Refs #62