code: public function unPublish()
      {
          $origStage = Versioned::get_stage();
          Versioned::set_stage('Live');
  
          // This way our ID won't be unset
          $clone = clone $this->owner->record;
          $clone->delete();
  
          Versioned::set_stage($origStage);
  
          return $this->owner->edit(Controller::curr()->getRequest());
      }
docs: Unpublishes the record
  
  @return HTMLText|ViewableData_Customised