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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>
    <pages>
      <page pageid="10" ns="0" title="PTL Trader Changelog" touched="2021-07-02T09:38:10Z" lastrevid="213" counter="113357" length="7216" />
      <page pageid="9" ns="0" title="PTL Trader Manual" touched="2021-07-02T09:28:24Z" lastrevid="210" counter="46916" length="11086" />
      <page pageid="38" ns="0" title="Pair Database" touched="2015-03-30T13:55:50Z" lastrevid="155" counter="68810" length="10236" />
      <page pageid="13" ns="0" title="Pair Trading Lab Algorithms &amp; Strategies" touched="2014-11-26T19:48:37Z" lastrevid="119" counter="39589" length="8198" />
      <page pageid="14" ns="0" title="Pair Trading Lab Portfolios" touched="2014-08-04T23:07:24Z" lastrevid="94" counter="35453" length="8920" />
      <page pageid="33" ns="0" title="Pair Trading Models" touched="2022-07-20T11:09:53Z" lastrevid="214" counter="173708" length="22895" />
      <page pageid="40" ns="0" title="Trading Pairs Based on Inverse ETFs" touched="2017-09-02T13:33:48Z" lastrevid="179" counter="43264" length="3516" />
    </pages>
  </query>
</api>