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HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <blocks>
      <block id="5" user="Blackdiamond1964" by="Windwalkr" timestamp="2021-05-19T03:18:30Z" expiry="infinity" reason="Inserting false information" nocreate="" autoblock="" />
      <block id="4" user="Valentinvladimirovic" by="Windwalkr" timestamp="2017-10-15T07:48:03Z" expiry="infinity" reason="Inserting nonsense/gibberish into pages" nocreate="" autoblock="" />
      <block id="3" user="206" by="Windwalkr" timestamp="2016-03-20T01:12:23Z" expiry="infinity" reason="Spamming links to external sites" nocreate="" autoblock="" />
      <block id="2" user="Fabartus" by="Jamesmoody" timestamp="2013-12-10T07:37:12Z" expiry="infinity" reason="Repeated CoC violations" nocreate="" autoblock="" />
      <block id="1" user="Tuksutin" by="Windwalkr" timestamp="2012-08-01T05:44:49Z" expiry="infinity" reason="Inserting nonsense/gibberish into pages" nocreate="" autoblock="" />
    </blocks>
  </query>
</api>