* @return obj
	 */
	public static function init( $quiz_id, $lesson_id, $student = null ) {

		$student = llms_get_student( $student );
		if ( ! $student ) {
			throw new Exception( __( 'You must be logged in to take a quiz!', 'lifterlms' ) );
		}

		// Initialize a new attempt.
		$attempt = new self();
		$attempt->set( 'quiz_id', $quiz_id );
		$attempt->set( 'lesson_id', $lesson_id );
		$attempt->set( 'student_id', $student->get_id() );
		$attempt->set_status( 'incomplete' );
		$attempt->set_questions( $attempt->get_new_questions() );

		$number = 1;

		$last_attempt = $student->quizzes()->get_last_attempt( $quiz_id );
		if ( $last_attempt ) {
			$number = absint( $last_attempt->get( 'attempt' ) ) + 1;
		}
		$attempt->set( 'attempt', $number );

		return $attempt;