Nevow (pronounced as the French "nouveau", or "noo-voh") is a web application construction kit written in Python. It is designed to allow the programmer to express as much of the view logic as desired in Python, and includes a pure Python XML expression syntax named stan to facilitate this. However it also provides rich support for designer-edited templates, using a very small XML attribute language to provide bi-directional template manipulation capability.

Nevow also includes formless, a declarative syntax for specifying the types of method parameters and exposing these methods to the web. Forms can be rendered automatically, and form posts will be validated and input coerced, rendering error pages if appropriate. Once a form post has validated successfully, the method will be called with the coerced values.

Features

• XHTML templates: contain no programming logic, only nodes tagged with nevow attributes
  
• data/render methods: simplify the task of separating data from presentation and writing view logic
  
• stan: An s-expression-like syntax for expressing xml in pure python
  
• Athena: Cross-browser JavaScript library for sending client side events to the server and server side events to the client after the page has loaded, without causing the entire page to refresh
  

• formless: (take a look at formal for an alternate form library) For describing the types of objects which may be passed to methods of your classes, validating and coercing string input from either web or command-line sources, and calling your methods automatically once validation passes.
  
• webform: For rendering web forms based on formless type descriptions, accepting form posts and passing them to formless validators, and rendering error forms in the event validation fails