code: def update(self, id, data):
          
          self.db.execute([
              'UPDATE comments SET',
              ','.join(key + '=' + '?' for key in data),
              'WHERE id=?;'],
              list(data.values()) + [id])
  
          return self.get(id)
docs: Update comment :param:`id` with values from :param:`data` and return
          updated comment.