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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>
    <blocks>
      <block id="1" user="5.79.131.106" by="Tmhafkamp" timestamp="2013-11-15T21:00:08Z" expiry="infinity" reason="" anononly="" nocreate="" />
    </blocks>
  </query>
</api>