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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>
    <allcategories accontinue="File_Formats_by_Game" />
  </query-continue>
  <query>
    <allcategories>
      <c size="3" pages="3" files="0" subcats="0" xml:space="preserve">Audio</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Audio Formats</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Documented File Formats</c>
      <c size="17" pages="17" files="0" subcats="0" xml:space="preserve">Donkey Kong Country: Tropical Freeze</c>
      <c size="35" pages="35" files="0" subcats="0" xml:space="preserve">Donkey Kong Country Returns</c>
      <c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Donkey Kong Country Returns 3D</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Donky Kong Country Returns</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">File Format</c>
      <c size="93" pages="90" files="0" subcats="3" xml:space="preserve">File Formats</c>
      <c size="2" pages="0" files="0" subcats="2" xml:space="preserve">File Formats by Completion</c>
    </allcategories>
  </query>
</api>