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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="403" ns="0" title="Main Page">
        <images>
          <im ns="6" title="File:GroupPhoto Jan26 2015.jpg" />
          <im ns="6" title="File:Oleg.jpg" />
          <im ns="6" title="File:SHPYRKO GROUP March2013.gif" />
          <im ns="6" title="File:UCSD Physics Department 2008.jpg" />
        </images>
      </page>
    </pages>
  </query>
</api>