title: How regex a empty string in python?
body: <p>I want that find empty tags, here is a example   </p>
  
  <pre><code>txt ="&lt;lol1&gt;&lt;&gt;&lt;lol2&gt;"
  rgx = "&lt;([a-zA-Z_0-9]+)&gt;"
  print re.findall(rgex, txt)
  </code></pre>
  
  <p>I get this</p>
  
  <pre><code>['lol1', 'lol2']
  </code></pre>
  
  <p>I want</p>
  
  <pre><code>['lol1', '', 'lol2']
  </code></pre>
  
  <p>How I can do this with regex?</p>