/**
* Implementation of custom clone method since
* native php __clone raises error in Flow.
* Override in exercises which have additional references to objects.
*/
public function postClone()
{
if (is_object($this->image)) {
$this->image = $this->image->copy();
}
if (is_object($this->pdfFile)) {
$this->pdfFile = $this->pdfFile->copy();
}
if (is_object($this->soundFile)) {
$this->soundFile = $this->soundFile->copy();
}
}
