/**
  * Begins the test session. Calling this method will make the state
  * change into AssessmentTestSessionState::INTERACTING.
  *
  * @qtism-test-interaction
  * @qtism-test-duration-update
  */
 public function beginTestSession()
 {
     $sessionMemento = $this->getSessionMemento();
     parent::beginTestSession();
     $this->triggerEventChange($sessionMemento);
 }