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Pylons and Pyramid

Web application framework

Pylons

Pylons is an open source web framework written in Python. It makes extensive use of the Web Server Gateway Interface standard to promote reusability and to separate functionality into distinct modules. 

Pylons has developed into the Pylons Project, and the old code from Pylons 1.0 is being supported indefinitely, however the newer iterations of Pylons has now been released as the Pyramid web framework.