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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>
    <allcategories>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Anonymous access</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Delete</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">English documentation</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Political party articles using deprecated parameters</c>
      <c size="14" pages="14" files="0" subcats="0" xml:space="preserve">WIP</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Wikipedia administration templates</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Wikipedia administrator statistics</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Οικονομικά στοιχεία 2012</c>
      <c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Σελίδες με κατεστραμμένες συνδέσεις</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Σελίδες με κατεστραμμένους συνδέσμους</c>
    </allcategories>
  </query>
</api>