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<?xml version="1.0"?>
<api>
  <query>
    <random>
      <page id="139" ns="0" title="Inducción Magnética (Fis1530 Fis 152 DS)" />
      <page id="536" ns="0" title="Lentes Delgados (Fiz0312)" />
    </random>
  </query>
</api>