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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.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <revisions rvcontinue="665" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1" ns="0" title="Main Page">
        <revisions>
          <rev user="Craig Peacock" timestamp="2018-07-04T09:47:56Z" comment="Added link for RAK833 LoRa Concentrator HAT" />
          <rev user="Craig Peacock" timestamp="2018-05-06T03:11:42Z" comment="Add link The Things Network Frequency Plan for Australia" />
          <rev user="Craig Peacock" timestamp="2018-05-06T02:15:00Z" comment="" />
          <rev user="Craig Peacock" timestamp="2017-06-18T03:36:43Z" comment="Added link to Watts Clever Smart Plug" />
          <rev user="Craig Peacock" timestamp="2017-06-17T12:31:35Z" comment="Added link for 12V SLA Low Voltage Disconnect" />
        </revisions>
      </page>
    </pages>
  </query>
</api>