docs: function addPrettify() {
    var els = document.querySelectorAll('pre');
    for (var i = 0, el; el = els[i]; i++) {
      if (!el.classList.contains('noprettyprint')) {
        el.classList.add('prettyprint');
      }
    }
    
    var el = document.createElement('script');
    el.type = 'text/javascript';
    el.src = PERMANENT_URL_PREFIX + 'prettify.js';
    el.onload = function() {
      prettyPrint();
    }
    document.body.appendChild(el);
  }