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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-continue>
    <allredirects arcontinue="Curso_Python_DGA_2011/servicios_web/introduccion" />
  </query-continue>
  <query>
    <allredirects>
      <r ns="0" title="Cagada" />
      <r ns="0" title="Ciencias naturales en la escuela primaria" />
      <r ns="0" title="Curso Python DGA 2011/Resumen Contenidos" />
      <r ns="0" title="Curso Python DGA 2011/acceso a datos/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/android/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/django/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/inmersion python/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/jython/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/pygame/introduccion" />
      <r ns="0" title="Curso Python DGA 2011/pyqt/introduccion" />
    </allredirects>
  </query>
</api>