title: Add class an element placed before another element
body: <p>Please help me to add class. my code is given below:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;p&gt;some conent goes here&lt;/p&gt;
  &lt;p&gt;some conent goes here&lt;/p&gt;
  &lt;p&gt;some conent goes here&lt;/p&gt;
  &lt;p&gt;some conent goes here&lt;/p&gt;
  
  &lt;ul&gt;
      &lt;li&gt;My list item&lt;/li&gt;
      &lt;li&gt;My list item&lt;/li&gt;
      &lt;li&gt;My list item&lt;/li&gt;
  &lt;/ul&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>I want to add a class on "p" just placed before the <code>&lt;ul&gt;</code></p>