You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
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<?xml version="1.0"?>
<api>
  <query>
    <exturlusage>
      <eu pageid="51" ns="0" title="Development" url="http://www.mediawiki.org/wiki/Extension:Anysite" />
      <eu pageid="63" ns="0" title="Ideas.and.notes" url="http://www.mediawiki.org/wiki/Manual:User_rights" />
    </exturlusage>
  </query>
</api>