code: def add_or_update(user_id, app_id, value):
          '''
          Editing evaluation.
          '''
          rec = MEvaluation.get_by_signature(user_id, app_id)
          if rec:
              entry = TabEvaluation.update(
                  value=value,
              ).where(TabEvaluation.uid == rec.uid)
              entry.execute()
          else:
              TabEvaluation.create(
                  uid=tools.get_uuid(),
                  user_id=user_id,
                  post_id=app_id,
                  value=value,
              f add_or_update(user_id, app_id, value):
          '''
          Editing evaluation.
          '''
          rec = MEvaluation.get_by_signature(user_id, app_id)
          if rec:
              entry = TabEvaluation.update(
                  value=value,
              ).where(TabEvaluation.uid == rec.uid)
              entry.execute()
          else:
              TabEvaluation.create(
                  uid=tools.get_uuid(),
                  user_id=user_id,
                  post_id=app_id,
                  value=value,
              )
docs: Editing evaluation.