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>
    <pages>
      <page pageid="5" ns="6" title="File:Twilight-formula.gif" imagerepository="local">
        <imageinfo>
          <ii timestamp="2009-02-12T10:08:07Z" user="Admin" />
        </imageinfo>
      </page>
    </pages>
  </query>
</api>