Homebrew Python and an entry in / Library / Python / 2.7 / site-packages /?

Question

Is there a definitive guide to installing Homebrew Python correctly, along with pip, virtualenv, virtualenvwrapper, etc.

I read the following pages:

https://github.com/mxcl/homebrew/wiki/Homebrew-and-Python
http://osxastrotricks.wordpress.com/2012/05/02/python-setup-with-homebrew/
http://skipperkongen.dk/2011/11/13/installing-django-in-virtual-environment-on-mac/
http://www.thisisthegreenroom.com/2011/installing-python-numpy-scipy-matplotlib-and-ipython-on-lion/
http://youshoulddoityourself.blogspot.com.au/2010/11/test.html

I have OSX 10.8 (Mountain Lion) DP3 and I installed the Xcode command line tools.

I also installed XQuartz, just in case (10.8 does not provide it).

Then I ran:

brew install python --universal --framework 

I added the following to ~/.bash_profile :

 export PATH="/usr/local/bin:/usr/local/share/python:${PATH}" 

Then I ran:

 sudo easy_install pip 

which seemed to work.

I check where pip is installed:

  Victors-MacBook-Pro:~ victorhooi$ which pip /usr/local/bin/pip 

However, when I try to install install packages, I get an error message that is at a loss that you cannot write to / Library / Python / 2.7 / site-packages:

 running install_lib creating /Library/Python/2.7/site-packages/yolk error: could not create '/Library/Python/2.7/site-packages/yolk': Permission denied ---------------------------------------- Command /usr/bin/python -c "import setuptools;__file__='/Users/victorhooi/build/yolk/setup.py';exec(compile(open(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --single-version-externally-managed --record /var/folders/gg/m37t1rkx4zj7z54ls487jfc40000gn/T/pip-ap7LSB-record/install-record.txt failed with error code 1 in /Users/victorhooi/build/yolk Storing complete log in /Users/victorhooi/Library/Logs/pip.log 

My understanding was that Homebrew Python would install its own site packages in it, and I would not have to weirdly roll around the entire file system tree to make it work?

Cheers, Victor

Answer 1

Please, as someone who was exactly where you are, first start using virtual environments, then click and the rest. They are amazing and will solve this and many future problems.

Answer 2

At the same time, home python has evolved:

• Python installed via brew no longer tries to write to /Library/Python .
• Homebrew Python now always uses its own site packages.
• pip (and distribution) is installed automatically.
• The -framework option is not required. Now Homebrew is the default.
• XQuartz is necessary (unfortunately) because Tk headers refer to X11 headers.

Your PATH in .bashrc is correct (and still necessary).

Answer 3

Now that there is Mountain Lion 10.8.2, and I have an outdated version of Python 2.7 from Lion, it just doesn't work. No matter what I tried, Python wanted to access / Library / .. Not good. A simple solution is brew uninstall python and then brew install python . Solves almost all Python-related issues with homebrew on ML.