docs: def collapse(self, id_user):
          """Collapse comment beloging to user."""
          c = CmtCOLLAPSED(id_bibrec=self.id_bibrec, id_cmtRECORDCOMMENT=self.id,
                           id_user=id_user)
          db.session.add(c)
          db.session.commit()