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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>
    <allcategories>
      <c size="4" pages="0" files="4" subcats="0" xml:space="preserve">Preset</c>
      <c size="3" pages="0" files="3" subcats="0" xml:space="preserve">PrintedMaps</c>
    </allcategories>
  </query>
</api>