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HTML is good for debugging, but probably is not suitable for your application.
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<?xml version="1.0"?>
<api>
  <query>
    <userinfo id="0" name="3.21.247.78" anon="">
      <groups />
      <rights>
        <r>createaccount</r>
        <r>read</r>
        <r>edit</r>
        <r>createpage</r>
        <r>createtalk</r>
        <r>writeapi</r>
      </rights>
    </userinfo>
  </query>
</api>