SQLAlchemy: Using raw SQL in ORM statements

sqlalchemy-raw-sql.py

#     ...
participants_and_editor = text(
    'ARRAY(SELECT DISTINCT UNNEST(array_cat('
    '   ARRAY[guidebook.feed_document_changes.user_id], :participants)) '
    'ORDER BY 1)')
DBSession.execute(
    DocumentChange.__table__.update().
    where(DocumentChange.document_id == outing_id).
    where(DocumentChange.change_id != existing_change.change_id).
    values(user_ids=participants_and_editor),
    {'participants': participant_ids}
)