code: def update_hidden_notes(self):
          
          if not self.tag_as_cern:
              notes = record_get_field_instances(self.record,
                                                 tag="595")
              for field in notes:
                  for dummy, value in field[0]:
                      if value == "CDS":
                          self.tag_as_cern = True
          record_delete_fields(self.record, tag="595")
docs: Remove hidden notes and tag a CERN if detected.