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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>
    <allpages apcontinue="Big_Brother_Obama_Is_Watching" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="636" ns="0" title="Bachmann Exposes $105 Billion Secret" />
      <p pageid="490" ns="0" title="Backlash Against Common Core" />
      <p pageid="576" ns="0" title="Bad Facts about Obama’s Prospects" />
      <p pageid="577" ns="0" title="Bailing out the European Union" />
      <p pageid="914" ns="0" title="Barbara Dolan Atherton" />
      <p pageid="491" ns="0" title="Battle for Control of the Republican Party Begins" />
      <p pageid="811" ns="0" title="Best Pillow For Your Comfort: Side Sleeper Neck Support Pillow" />
      <p pageid="205" ns="0" title="Best arguments 2017" />
      <p pageid="207" ns="0" title="Betsy DeVos" />
      <p pageid="578" ns="0" title="Beware of the Lame Duck Session" />
    </allpages>
  </query>
</api>