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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"?>
<api>
  <query-continue>
    <allcategories accontinue="Alleyways" />
  </query-continue>
  <query>
    <allcategories>
      <c size="25" pages="25" files="0" subcats="0" xml:space="preserve">!Artigos com mudança proposta para o Centro de Ajuda</c>
      <c size="2" pages="2" files="0" subcats="0" xml:space="preserve">!Artigos em processo de criação</c>
      <c size="67" pages="62" files="0" subcats="5" xml:space="preserve">!Objects to move to Brazilian wiki</c>
      <c size="0" pages="0" files="0" subcats="0" xml:space="preserve">!Objects to move to brazilian wiki</c>
      <c size="2" pages="0" files="2" subcats="0" xml:space="preserve">Add Place</c>
      <c size="4" pages="4" files="0" subcats="0" xml:space="preserve">Add Wikilinks</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Advanced app content</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Alabama</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Alaska</c>
      <c size="47" pages="44" files="0" subcats="3" xml:space="preserve">All articles containing potentially dated statements</c>
    </allcategories>
  </query>
</api>