code: def set_preserver_info(self, sample):
          
          if sample.getPreserver() and sample.getDatePreserved():
              # Preserver and Date Preserved already set. This is correct
              return True
          preserver = self.get_form_value("Preserver", sample,
                                          sample.getPreserver())
          preserved = self.get_form_value("getDatePreserved",
                                          sample.getDatePreserved())
          if not all([preserver, preserved]):
              return False
          sample.setPreserver(preserver)
          sample.setDatePreserver(DateTime(preserved))
          return True
docs: Updates the Preserver and the Date Preserved with the values provided
          in the request. If neither Preserver nor DatePreserved are present in
          the request, returns False