Some useful Python packages and links.
Tutorials
Practical Python for Astronomers
Python 2.7 Quick Reference sheet
SciPy Cookbook
Matplotlib Thumbail gallery
seaborn for data visualization
Astropy : Growing selection of useful python packages for astronomers (Formally Astrolib)
pysynphot : Useful package to resample spectra (now part of astropy)
Some "simple" Astronomy scripts (no need for big packages)
Some online references
A list of references among which the following of often appreciated:
* Automate boring stuffs (free pdf)
* Learn python the hard way: this is basically various exercises to learn by practicing.
Apprendre à programmer avec Python (in "FRENCH") of Gérard Swinnen (troisième et cinquième éditions ; previously published by O'Reilly but now by Eyrolles; ISBN 978-2-212-13434-6)
Introduction a python pour la programmation scientifique (in "FRENCH")
Useful Packages (not all tested)
MCMC (EMCEE)
Pyevolve - Genetic Algorithm
AstroML: Machine Learning and data Mining for astronomy
Fisher Matrices (Dan Coe)
Trilogy to create color images from fits (Dan Coe)
Scientific Python (not SciPy)
VPython for 3D graphs