Install both Python 2.7 and Python 3.3 on Windows

Posted by in Python

I am working hard with Python since a few months ago, improving my skills. If you have decided to try, you can notice there are two main Python version: 2.7.5 and 3.3.2 afeter visiting the download page, you . You can read about whether you need one or another , but the truth is that there are several differences between them. So be aware of what you need.

Installing Python on Windows

But the question is .. is it possible to have installed both Python versions under the same Windows machina? The answer is yes. , mainly because of Python’s installers, that advice you to install them on c:\python27 and c:\python33.

The question is … which one is the default Python version? To know it, just open a MS-DOS windows and type “Python”:

Versión de Python

Versión de Python

you can check that the default Python version is 3.3. And what if I want Python 2.7 as a default?

Step 1, renaming Python 3.3

The first step is an easy one, just rename the files python.exe y pythonw.exe undeer Python 3.3 directory:

Cambiando Python.exe

Cambiando Python.exe

Step 2, verify environment variables

Before continue, let’s verify our environment variables de entorno if Pythons dirs are included in the Path variable. Right clic on My PC, properties and select Advances Options:

Variables de entorno

Variables de entorno

Variables de entorno

Variables de entorno

Clic on Environment variables, and find if the PATH variable includes c:\Python33 and c:\Python27, . If they are not, add it, separated by semicolon.

Path

Path

Cambiando el PATH

Cambiando el PATH

Now, open a new MS-DOS command line and type Python:

Python 2.7 por defecto

Python 2.7 por defecto

Now you can see python 2.7.3 is the default one!

But …. can I work with Python 3.3? Yes, and is as simply as call “python33” (remember, we renamed on step 1)

Abriendo Python 3.3

Abriendo Python 3.3

I hope it can be useful for you!