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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="ThumbnailEditor.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1976" ns="6" title="File:TechNet-Active Directory Best Practices.pdf" imagerepository="local">
        <imageinfo>
          <ii timestamp="2016-03-10T17:35:05Z" user="Ledhed" />
        </imageinfo>
      </page>
      <page pageid="1977" ns="6" title="File:TechNet-Best Practice Active Directory Design for Managing Windows Networks.pdf" imagerepository="local">
        <imageinfo>
          <ii timestamp="2016-03-10T18:00:25Z" user="Ledhed" />
        </imageinfo>
      </page>
      <page pageid="1978" ns="6" title="File:TechNet-Designing OU Structures that Work Choosing the Best Model.pdf" imagerepository="local">
        <imageinfo>
          <ii timestamp="2016-03-10T18:10:31Z" user="Ledhed" />
        </imageinfo>
      </page>
      <page pageid="1985" ns="6" title="File:TechNet-Establishing Group Policy Operational Guidelines.pdf" imagerepository="local">
        <imageinfo>
          <ii timestamp="2016-03-10T18:52:37Z" user="Ledhed" />
        </imageinfo>
      </page>
    </pages>
  </query>
</api>