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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="2011年秋课程总结" />
  </query-continue>
  <query>
    <allcategories>
      <c size="3" pages="3" files="0" subcats="0" xml:space="preserve">' .. cat .. '</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">100分钟教案</c>
      <c size="101" pages="101" files="0" subcats="0" xml:space="preserve">2010年春教案</c>
      <c size="112" pages="112" files="0" subcats="0" xml:space="preserve">2010年春课程总结</c>
      <c size="130" pages="130" files="0" subcats="0" xml:space="preserve">2010年秋教案</c>
      <c size="1" pages="1" files="0" subcats="0" xml:space="preserve">2010年秋课程</c>
      <c size="116" pages="116" files="0" subcats="0" xml:space="preserve">2010年秋课程总结</c>
      <c size="81" pages="81" files="0" subcats="0" xml:space="preserve">2011年春教案</c>
      <c size="95" pages="95" files="0" subcats="0" xml:space="preserve">2011年春课程总结</c>
      <c size="20" pages="20" files="0" subcats="0" xml:space="preserve">2011年秋教案</c>
    </allcategories>
  </query>
</api>