Pimcore\Model\Object\Concrete::getValueForFieldName PHP Method

    public function getValueForFieldName($key)
    {
        if (isset($this->{$key})) {
            return $this->{$key};
        } elseif ($this->getClass()->getFieldDefinition($key) instanceof Model\Object\ClassDefinition\Data\CalculatedValue) {
            $value = new Model\Object\Data\CalculatedValue($key);
            $value = Service::getCalculatedFieldValue($this, $value);
            return $value;
        }
        return false;
    }