My Adventures in Coding

September 11, 2011

Python – Upgrading Python with easy_install, pip, and virtualenv on a Mac

Filed under: Mac,Python — Brian @ 1:45 pm
Tags: , ,

For this tutorial I am upgrading from python 2.6 to python 2.7 on my Mac. Every time I have to upgrade Python versions, it always takes me a few minutes to remember the steps since I do this task so rarely. So here is a simple set of instructions that seem to work for me!

Install python 2.7

  • Download the Python Mac dmg file from the Python Downloads page
    Just open the dmg and follow the installer as you would with any application
  • You should now have Python 2.7 installed in:
    /Library/Frameworks/Python.framework/Versions/2.7/bin/python

NOTE: Even though we have installed python 2.7, your /usr/bin/python is still pointing to an older version of Python, so for example if you run easy_install, if will run from the older version of Python, and install packages into the library of the old Python installation.

So, on to step two of the install:
Let’s switch the /usr/bin/python link to point to the newest version of Python, and at the same time let’s create a soft link in the Python install folder that always points to the current install of Python. So the next time we upgrade, we will only need to change the “Current” version link.

#Create a soft link in /Library/Frameworks/Python.framework/Versions/
cd /Library/Frameworks/Python.framework/Versions/
ln -s 2.7 Current

#Switch the /usr/bin/python link to point to current python link
cd /usr/bin
rm -f python
ln -s /Library/Frameworks/Python.framework/Versions/Current/bin/python python

Install Setup Tools (this includes easy_install)

Download the egg file for your version of python (for this example, 2.7) from the Setup Tools Downloads page. To install setup tools just run the egg file like any other shell script:

sudo sh setuptools-0.6c11-py2.7.egg

Install pip (Using easy_install)

Open a new Terminal window session. You will need a new terminal session for easy_install to show up on the path.

sudo easy_install pip

Now we can install any python packages we want using pip!

Install Virtualenv (Using pip)

Now that we have pip, lets install a very important package called virtualenv!

pip install virtualenv

Thats it!

Now you will have Python 2.7 on your Mac, with easy_install, pip, and virtualenv ready to go.

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