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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>
    <prefixsearch>
      <ps ns="0" title="Meaning Attributes Kinds And Exactly How Do They Work." pageid="745366" />
      <ps ns="0" title="Meaning Attributes Kinds And How Do They Function." pageid="828231" />
      <ps ns="0" title="Meaning Attributes Kinds And Just How Do They Function." pageid="775072" />
      <ps ns="0" title="Meaning Attributes Types And Exactly How Do They Function." pageid="24373" />
      <ps ns="0" title="Meaning Attributes Types And Exactly How Do They Work." pageid="24594" />
      <ps ns="0" title="Meaning Attributes Types And How Do They Work." pageid="24288" />
      <ps ns="0" title="Meaning Attributes Types And Just How Do They Function." pageid="825785" />
      <ps ns="0" title="Meaning Characteristics Kinds And Exactly How Do They Function." pageid="741314" />
      <ps ns="0" title="Meaning Characteristics Kinds And How Do They Function." pageid="39294" />
      <ps ns="0" title="Meaning Characteristics Kinds And Just How Do They Work." pageid="837523" />
    </prefixsearch>
  </query>
</api>