protected function make_blocked_question_placeholder($slot) {
        $replacedquestion = $this->get_question_attempt($slot)->get_question();

        question_bank::load_question_definition_classes('description');
        $question = new qtype_description_question();
        $question->id = $replacedquestion->id;
        $question->category = null;
        $question->parent = 0;
        $question->qtype = question_bank::get_qtype('description');
        $question->name = '';
        $question->questiontext = get_string('questiondependsonprevious', 'quiz');
        $question->questiontextformat = FORMAT_HTML;
        $question->generalfeedback = '';
        $question->defaultmark = $this->quba->get_question_max_mark($slot);
        $question->length = $replacedquestion->length;
        $question->penalty = 0;
        $question->stamp = '';
        $question->version = 0;
        $question->hidden = 0;
        $question->timecreated = null;
        $question->timemodified = null;
        $question->createdby = null;
        $question->modifiedby = null;

        $placeholderqa = new question_attempt($question, $this->quba->get_id(),
                null, $this->quba->get_question_max_mark($slot));
        $placeholderqa->set_slot($slot);
        $placeholderqa->start($this->get_quiz()->preferredbehaviour, 1);
        $placeholderqa->set_flagged($this->is_question_flagged($slot));
        return $placeholderqa;
    }