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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>
    <allimages gaicontinue="Customized_Logs_Rev_1.11.zip" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1587" ns="6" title="File:1971 Toronto Star Weekly - Lewis Parker pg 1 sample.jpg" />
      <page pageid="1435" ns="6" title="File:1996 John Eldon McFadyen - Senior Citizen of the Year.jpg" />
      <page pageid="1389" ns="6" title="File:Abraham Allan Atkinson and Annie.jpg" />
      <page pageid="1386" ns="6" title="File:Abraham Nelson, Mary, Archie Atkinson.jpg" />
      <page pageid="1390" ns="6" title="File:Atkinson - Herb and Mabel.jpg" />
      <page pageid="1391" ns="6" title="File:Atkinson - Ross, John, Archie.jpg" />
      <page pageid="1381" ns="6" title="File:Bruce County.jpg" />
      <page pageid="1548" ns="6" title="File:Customized Logs Rev 1.0.zip" />
      <page pageid="1552" ns="6" title="File:Customized Logs Rev 1.1.zip" />
      <page pageid="1672" ns="6" title="File:Customized Logs Rev 1.10.zip" />
    </pages>
  </query>
</api>