How does wikipedia generates PDF

I would like to know on how wikipedia (http://en.wikipedia.org/) creates PDF? It seem to be using some application at the back-end. Could a开发者_如何学运维nyone please let me know on how this is done?

Thanks

Srikanth

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Wikipedia runs Mediawiki.
A Google check tells me that they have two PDF extensions.
This one is the one who's still mantained: PDF_Writer

It doesn't use a PHP HTML→PDF generator, (though there are some)
It actually does something trickier and more clever.

The PDF Writer uses the Python Reportlab libraries to generate PDF based on a DOM derived from parsing mediawiki-markup using the mwlib parser.

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To confirm ZJR's answer, these are the document properties: