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HTML is good for debugging, but is unsuitable for application use.
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To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
    <allfileusages afcontinue="Feed-icon.png|51" />
      <f fromid="424" ns="6" title="File:Burka on the job - Crossing guard in Alberta.jpg" />
      <f fromid="1" ns="6" title="File:Cloud icon.jpg" />
      <f fromid="360" ns="6" title="File:Commons-logo.svg" />
      <f fromid="149" ns="6" title="File:Communism - Nazism - Feminism.svg" />
      <f fromid="434" ns="6" title="File:Der dressierte Mann.jpg" />
      <f fromid="434" ns="6" title="File:Der dressierte Mann (Die Trilogie).jpg" />
      <f fromid="434" ns="6" title="File:Die 25-Stunden-Woche.jpg" />
      <f fromid="385" ns="6" title="File:Disambig-dark.png" />
      <f fromid="434" ns="6" title="File:Esther Vilar 1975.jpg" />
      <f fromid="434" ns="6" title="File:Esther Vilar 2005.jpg" />