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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="Wikipedia_books_(community_books)" />
  </query-continue>
  <query>
    <allcategories>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Annotated image templates</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Books</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Graphic templates</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">MiniTT1 and FlexTT5</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">MiniTT1 and FlexTT5:1</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Pages with broken file links</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Template documentation</c>
      <c size="21" pages="21" files="0" subcats="0" xml:space="preserve">Template sandboxes</c>
      <c size="23" pages="23" files="0" subcats="0" xml:space="preserve">Templates with print versions</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Unprintworthy redirects</c>
    </allcategories>
  </query>
</api>