docs: def marvcli_comment_list(datasets):
      """Lists comments for datasets.
  
      Output: setid comment_id date time author message
      """
      app = create_app()
      ids = parse_setids(datasets, dbids=True)
      comments = db.session.query(Comment)\
                           .options(db.joinedload(Comment.dataset))\
                           .filter(Comment.dataset_id.in_(ids))
      for comment in sorted(comments, key=lambda x: (x.dataset._setid, x.id)):
          print(comment.dataset.setid, comment.id,
                datetime.datetime.fromtimestamp(int(comment.time_added / 1000)),
                comment.author, repr(comment.text))