/**
  * {@inheritDoc}
  * @return array
  */
 public function __sleep()
 {
     $properties = array_merge(array('__isInitialized__'), parent::__sleep());
     if ($this->__isInitialized__) {
         $properties = array_diff($properties, array_keys($this->__getLazyProperties()));
     }
     return $properties;
 }