ipython - an interactive computing environment
http://ipython.scipy.org/moin/
bpython - bpython is a fancy interface to the Python interpreter for Unix-like operating systems
http://bpython-interpreter.org/
skeleton - Basic Template system for project skeleton.
http://pypi.python.org/pypi/skeleton/
modern-package-package - PasteScript template to create a Python project with distribute and buildout support
http://pypi.python.org/pypi/modern-package-template/
numpy - NumPy is the fundamental package needed for scientific computing with Python
http://numpy.scipy.org/
Scipy - SciPy (pronounced "Sigh Pie") is open-source software for mathematics, science, and engineering
http://www.scipy.org/
matplotlib - matplotlib is a python 2D plotting library which produces publication quality figures in a variety of hardcopy formats and interactive environments across platforms
http://matplotlib.sourceforge.net/
pyqt - PyQt is a comprehensive set of Python bindings for the Qt cross-platform GUI/XML/SQL C++ framework from Nokia's Qt Development Frameworks (formerly Trolltech)
http://wiki.python.org/moin/PyQt4
PySide - The PySide project provides LGPL-licensed Python bindings for the Qt cross-platform application and UI framework
http://www.pyside.org/
pygtk - PyGTK lets you to easily create programs with a graphical user interface using the Python programming language
http://www.pygtk.org/
wxPython - Welcome to the home of wxPython, a blending of the wxWidgets C++ class library with the Python programming language http://www.wxpython.org/
PyObjC - The PyObjC project aims to provide a bridge between the Python and Objective-C programming languages
The most important usage of this is writing Cocoa GUI applications on Mac OS X in pure Python
http://pyobjc.sourceforge.net/
Xapian / xappy - A Python module providing an easy-to-use layer on top of the Xapian search engine
http://code.google.com/p/xappy/
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