lib/Yucca/Component/Iterator/Iterator.php
protected function initializeModel($id, $shardingKey = null)
    {
        if (is_null($this->model)) {
            $this->model = $this->entityManager->load($this->modelClassName, $id, $shardingKey);
        }

        return $this;
    }
protected function initializeModel($id, $shardingKey = null)
    {
        if (is_null($this->model)) {
            $this->model = $this->entityManager->load($this->modelClassName, $id, $shardingKey);
        }

        return $this;
    }
initialize the unique model
@param mixed $id
@param mixed $shardingKey

@return self