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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="2" user="Zxcv" by="Admin" timestamp="2017-01-16T07:55:11Z" expiry="infinity" reason="" />
      <block id="1" user="Tuka" by="Admin" timestamp="2017-01-16T07:54:56Z" expiry="infinity" reason="" />
    </blocks>
  </query>
</api>