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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>
    <allusers>
      <u name="Александр Анишин" userid="2" />
      <u name="Евгений Тишин" userid="4" />
      <u name="Николай Сабуров" userid="5" />
      <u name="Сергей Кисиль" userid="3" />
      <u name="Сергей Крюков" userid="1" />
    </allusers>
  </query>
</api>