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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.
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<?xml version="1.0"?>
<api>
<query-continue>
<allcategories accontinue="На_модерацию" />
</query-continue>
<query>
<allcategories>
<c size="3" pages="3" files="0" subcats="0" xml:space="preserve">Аксессуары</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Википедия:Шаблоны:Внешние ссылки</c>
<c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Википедия:Шаблоны для документирования шаблонов</c>
<c size="7" pages="7" files="0" subcats="0" xml:space="preserve">Группы</c>
<c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Журналажа</c>
<c size="6" pages="6" files="0" subcats="0" xml:space="preserve">Знаменитые запаленные залазы</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Ксенобиология</c>
<c size="26" pages="26" files="0" subcats="0" xml:space="preserve">Мемы</c>
<c size="36" pages="36" files="0" subcats="0" xml:space="preserve">Места</c>
<c size="1" pages="0" files="0" subcats="1" xml:space="preserve">На кислофикацию</c>
</allcategories>
</query>
</api>