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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>
<allcategories>
<c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Books</c>
<c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Communication design</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Pages with broken file links</c>
<c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Templates</c>
<c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Web design</c>
<c size="0" pages="0" files="0" subcats="0" xml:space="preserve">Website design</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Wikipedia books (books without cover images)</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Wikipedia books (books without custom colors)</c>
<c size="1" pages="1" files="0" subcats="0" xml:space="preserve">Wikipedia books (community books)</c>
<c size="2" pages="2" files="0" subcats="0" xml:space="preserve">Wikipedia books (community books with bugs)</c>
</allcategories>
</query>
<query-continue>
<allcategories accontinue="Wikipedia_books_(incorrectly_categorized_books)" />
</query-continue>
</api>