code: function init() {
      var i, j;
  
      // Make collapse buttons clickable
      var buttons = document.querySelectorAll('.collapse-button');
      for (i = 0; i < buttons.length; i++) {
          buttons[i].onclick = toggleCollapseButton;
  
          // Show by default? Then toggle now.
          if (buttons[i].className.indexOf('show') !== -1) {
              toggleCollapseButton({target: buttons[i].children[0]});
          }
      }
  
      var responseCodes = document.querySelectorAll('.example-names');
      for (i = 0; i < responseCodes.length; i++) {
          var tabButtons = childrenByClass(responseCodes[i], 'tab-button');
          for (j = 0; j < tabButtons.length; j++) {
              tabButtons[j].onclick = toggleTabButton;
  
              // Show by default?
              if (j === 0) {
                  toggleTabButton({target: tabButtons[j]});
              }
          }
      }
  
      // Make nav items clickable to collapse/expand their content.
      var navItems = document.querySelectorAll('nav .resource-group .heading');
      for (i = 0; i < navItems.length; i++) {
          navItems[i].onclick = toggleCollapseNav;
  
          // Show all by default
          toggleCollapseNav({target: navItems[i].children[0]});
      }
  }
docs: /*
  Initialize the interactive functionality of the page.