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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="1933_births" />
  </query-continue>
  <query>
    <allcategories>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1855 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1865 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1876 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1887 births</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">1910 births</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">1911 Britannica templates</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1917 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1921 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1923 births</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">1926 deaths</c>
    </allcategories>
  </query>
</api>