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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>
    <allimages>
      <img name="BengtssonH_20170511-future,RConsortium,flat.pdf" timestamp="2017-05-12T02:52:32Z" user="Indrajit roy" url="https://wiki.r-consortium.org/images/2/25/BengtssonH_20170511-future%2CRConsortium%2Cflat.pdf" descriptionurl="https://wiki.r-consortium.org/view/File:BengtssonH_20170511-future,RConsortium,flat.pdf" ns="6" title="File:BengtssonH 20170511-future,RConsortium,flat.pdf" />
      <img name="MovingParts_Visual.PNG" timestamp="2017-01-21T15:16:20Z" user="MeharPratapSingh" url="https://wiki.r-consortium.org/images/2/2c/MovingParts_Visual.PNG" descriptionurl="https://wiki.r-consortium.org/view/File:MovingParts_Visual.PNG" ns="6" title="File:MovingParts Visual.PNG" />
      <img name="Initial_Path_Visual.PNG" timestamp="2017-01-21T15:16:20Z" user="MeharPratapSingh" url="https://wiki.r-consortium.org/images/0/03/Initial_Path_Visual.PNG" descriptionurl="https://wiki.r-consortium.org/view/File:Initial_Path_Visual.PNG" ns="6" title="File:Initial Path Visual.PNG" />
      <img name="Tux.png" timestamp="2016-05-18T18:14:57Z" user="Jfarwell" url="https://wiki.r-consortium.org/images/a/af/Tux.png" descriptionurl="https://wiki.r-consortium.org/view/File:Tux.png" ns="6" title="File:Tux.png" />
      <img name="Tux6.png" timestamp="2016-05-18T18:14:56Z" user="Jfarwell" url="https://wiki.r-consortium.org/images/8/82/Tux6.png" descriptionurl="https://wiki.r-consortium.org/view/File:Tux6.png" ns="6" title="File:Tux6.png" />
    </allimages>
  </query>
</api>