Can't pip install virtualenv in OS X 10.8 with brewed python 2.7

Question

When trying to install virtualenv using a brewed python, I get the following error:

$ pip install virtualenv
Requirement already satisfied (use --upgrade to          


        

Answer 1

I found that unlike you my paths were wrong according to brew doctor. But after correcting that I still had the issue (no surprises given your description) so I uninstalled virtualenv then reinstalled but this time with sudo, sudo pip install virtualenv

This resolved the issue, which indicates that I've either got another problem with the system configuration in general or someone who has more then my one hour of Python experience will be able to point out why it's not good (I think it's related to global installing being considered a bad practice).

Seth is onto something with which seems you see the same as me,

~ which python results in /usr/local/bin/python

~ ls -l /usr/local/bin/python gives me _permissions_etc_ /usr/local/bin/python -> ../Cellar/python/2.7.5/bin/python

Pip

which pip pointed to /usr/local/bin/pip

ls -l /usr/local/bin/pip shows _permissions_etc_ /usr/local/bin/pip -> ../Cellar/python/2.7.5/bin/pip

Virtualenv (I don't have an output prior to the sudo pip install)

which virtualenv is /usr/local/bin/virtualenv

ls -l /usr/local/bin/virtualenv shows _permissions_etc_ /usr/local/bin/virtualenv

When I created and use a virtualenv I get the following,

workon ve_test
which python
/Users/_username_/.virtualenvs/ve_test/bin/python
(ve_test)➜  ~PIP_VIRTUALENV_BASE  python --version
Python 2.7.5

FWIW my .zshrc has the following,

# Python related
# http://hackercodex.com/guide/python-virtualenv-on-mac-osx-mountain-lion-10.8/
# http://docs.python-guide.org/en/latest/dev/virtualenvs.html
source /usr/local/bin/virtualenvwrapper.sh
# virtualenv should use Distribute instead of legacy setuptools
export VIRTUALENV_DISTRIBUTE=true
# Centralized location for new virtual environments
export PIP_VIRTUALENV_BASE=$HOME/Projects/PythonVirtualEnv
# cache pip-installed packages to avoid re-downloading
export PIP_DOWNLOAD_CACHE=$HOME/.pip/cache