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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>
    <allfileusages gafcontinue="Bandeau-retraite-EN.png|4495" />
  </query-continue>
  <query>
    <pages>
      <page pageid="2209" ns="0" title="Autopano Tour" />
      <page pageid="2285" ns="0" title="APT v1.0 Hotspots editor window" />
      <page pageid="2287" ns="0" title="APT v1.0 3D Editor Window" />
      <page pageid="5635" ns="0" title="Understanding the RMS value" />
      <page pageid="6231" ns="0" title="Understanding the RMS value - 370" />
      <page pageid="6902" ns="0" title="GoPro VR Player - Getting started" />
    </pages>
  </query>
</api>