code: function query (el) {
    if (typeof el === 'string') {
      var selected = document.querySelector(el);
      if (!selected) {
        process.env.NODE_ENV !== 'production' && warn(
          'Cannot find element: ' + el
        );
        return document.createElement('div')
      }
      return selected
    } else {
      return el
    }
  }
docs: /* 
  Query an element selector if it's not an element already.