title: Change parent in xml by Python (lxml)
body: <p>Hi I am parsing and completely modifying XML file in Python3 using lxml and I need put new Element into existing Elements and change their parent.</p>
  
  <p>Example:
  old xml </p>
  
  <pre><code>&lt;a&gt;
    &lt;b&gt;something&lt;/b&gt;
    &lt;c&gt;something different&lt;/c&gt;
  &lt;/a&gt;
  </code></pre>
  
  <p>new xml</p>
  
  <pre><code>&lt;a&gt;
    &lt;new_parent&gt;
      &lt;b&gt;something&lt;/b&gt;
      &lt;c&gt;something different&lt;/c&gt;
    &lt;/new_parent&gt;
  &lt;a&gt;
  </code></pre>
  
  <p>Is it possible ?</p>