why i love PHP :D

CombinedForm.php

<?php  
public function getOriginalEntity(string $entity_class_name) : ?Model
  {
      if(array_key_exists($entity_class_name, $this->entities)) {
          $entity = $this->entities[ $entity_class_name ];
          //copy properties from stdEntity to this entity
          $stdEntity = $this->getEntity();
          foreach($this->entityProperties[ $entity_class_name ] as $property) {
              $entity->{$property} = $stdEntity->{$property};
          }

          return $entity;
      }

      return null;
  }