How do I find the location of my site-packages directory?
This should work on all distributions in and out of virtual environment due to it's "low-tech" nature. The os module always resides in the parent directory of 'site-packages'
import os; print(os.path.dirname(os.__file__) + '/site-packages')
To change dir to the site-packages dir I use the following alias (on *nix systems):
alias cdsp='cd $(python -c "import os; print(os.path.dirname(os.__file__))"); cd site-packages'