You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <blocks bkcontinue="20120602072854|116" />
  </query-continue>
  <query>
    <blocks>
      <block id="139" user="Zagith" by="Nererue" timestamp="2015-03-26T19:02:44Z" expiry="infinity" reason="" nocreate="" autoblock="" />
      <block id="138" user="Lyiss" by="Mereth" timestamp="2015-02-17T21:27:57Z" expiry="infinity" reason="Ban" />
      <block id="136" user="Emir04xd1288" by="Merak" timestamp="2014-11-14T19:39:34Z" expiry="infinity" reason="Vandalismo" nocreate="" autoblock="" noemail="" />
      <block id="134" user="183829282" by="LordJohn" timestamp="2014-11-10T01:00:49Z" expiry="infinity" reason="Vandalismo" nocreate="" autoblock="" noemail="" />
      <block id="130" user="Emir04xd123" by="Merak" timestamp="2014-11-01T20:13:29Z" expiry="infinity" reason="Linguaggio non consono" nocreate="" autoblock="" noemail="" />
      <block id="126" user="Big master" by="Leggendario" timestamp="2012-08-24T10:48:34Z" expiry="infinity" reason="Inserimento di contenuti privi di senso" nocreate="" autoblock="" />
      <block id="124" user="Bubuan97" by="Leggendario" timestamp="2012-08-17T12:37:02Z" expiry="infinity" reason="" nocreate="" autoblock="" />
      <block id="122" user="TomtomstA" by="LordJohn" timestamp="2012-06-06T15:11:18Z" expiry="infinity" reason="Collegamenti promozionali a siti esterni" nocreate="" autoblock="" />
      <block id="120" user="Hupp" by="LordJohn" timestamp="2012-06-04T21:42:17Z" expiry="infinity" reason="Inserimento di contenuti privi di senso" nocreate="" autoblock="" />
      <block id="118" user="Perla865" by="LordJohn" timestamp="2012-06-04T08:47:44Z" expiry="infinity" reason="Inserimento di contenuti privi di senso" nocreate="" autoblock="" />
    </blocks>
  </query>
</api>