private function addNode($answers, $node_type, $ask = '', array $attributes = [])
    {
        $node = Node::where(['type' => $node_type, 'pattern' => $ask])->first();

        if (is_null($node)) {
            $node = Node::create(array_merge([
                'type' => $node_type,
                'pattern' => $ask,
                'answers' => $answers,
            ], $attributes));
        } else {
            $node->answers = $answers;

            // Allows people set attributes
            foreach ($attributes as $key => $value) {
                if (!in_array($key, ['type', 'pattern', 'answers'])) {
                    $node->$key = $value;
                }
            }

            $node->save();
        }

        return $node;
    }