/**
  * Get the ChangeSetItems that reference a passed DataObject
  *
  * @param DataObject $object
  * @return DataList
  */
 public static function get_for_object($object)
 {
     return ChangeSetItem::get()->filter(['ObjectID' => $object->ID, 'ObjectClass' => $object->baseClass()]);
 }
 /**
  * Build identifying string key for this object
  *
  * @param DataObject $item
  * @return string
  */
 protected function implicitKey(DataObject $item)
 {
     if ($item instanceof ChangeSetItem) {
         return $item->ObjectClass . '.' . $item->ObjectID;
     }
     return $item->baseClass() . '.' . $item->ID;
 }