title: Getting attribute from an xml tag with xpath
body: <p>I have an xml file, I use the xpath <code>/content</code> which returns the following line:</p>
  
  <pre><code>&lt;content xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/&gt;
  </code></pre>
  
  <p>How can I get the type 'nil'? I am trying to write a test which will check if the content is empty, if there is no conten it will say nil="true" otherwise it will give the type e.g. xsi:type="String">true
  
  <p>I've tried //content[@xsi] and //content/xsi but still can't limit it down to just the part I want.</p>
  
  <p>I could just get a substring but I think there must be a way to do it with xpath. </p>