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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>
    <allimages gaicontinue="1C_Disc_Week_7_Solutions.pdf" />
  </query-continue>
  <query>
    <pages>
      <page pageid="4935" ns="6" title="File:1A Discussion Week 1.pdf" />
      <page pageid="4939" ns="6" title="File:1A Discussion Week 2.pdf" />
      <page pageid="4938" ns="6" title="File:1A Discussion Week 2 (by Xueping Long).pdf" />
      <page pageid="4968" ns="6" title="File:1A Final Review.pdf" />
      <page pageid="5024" ns="6" title="File:1C Disc Week 1 Solutions simple.pdf" />
      <page pageid="5011" ns="6" title="File:1C Disc Week 2 Solutions.pdf" />
      <page pageid="5012" ns="6" title="File:1C Disc Week 3 Solutions.pdf" />
      <page pageid="5013" ns="6" title="File:1C Disc Week 4 Solutions.pdf" />
      <page pageid="5015" ns="6" title="File:1C Disc Week 5 Solutions.pdf" />
      <page pageid="5016" ns="6" title="File:1C Disc Week 6 Solutions.pdf" />
    </pages>
  </query>
</api>