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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.
See the complete documentation, or API help for more information.
<?xml version="1.0"?>
<api>
  <query-continue>
    <allfileusages gafcontinue="BAS_Rene_Margritte.jpg" />
  </query-continue>
  <query>
    <pages>
      <page ns="6" title="File:BASF Werk Ludwigshafen 1881.JPG" missing="" />
      <page pageid="143692" ns="6" title="File:B&amp;B Red Panda.jpg" />
      <page pageid="163212" ns="6" title="File:B-57.jpg" />
      <page pageid="77542" ns="6" title="File:B. Fed Flag.PNG" />
      <page pageid="204796" ns="6" title="File:B025ccbbc9b30919488bb31400f77c68.jpg" />
      <page pageid="203718" ns="6" title="File:B1d99578baba0452632e37f743462d72.jpg" />
      <page pageid="203881" ns="6" title="File:B2185ed5c6d0bb6a10ffdbaf82b9e66c.jpg" />
      <page pageid="192738" ns="6" title="File:B3701482-4E09-46E1-9E1D-30142452BA1E.png" />
      <page pageid="183292" ns="6" title="File:B3t.jpeg" />
      <page pageid="219749" ns="6" title="File:BAF roundel.png" />
    </pages>
  </query>
</api>