How do you correctly set the PYTHONPATH variable on Windows?

Question

Whenever I try to expirement with Python on Windows, I always run into a wall with the import statements. Python simply can't find anything on Windows -- every import, even for something as core as timezone fails.

I know this has something to do with the PYTHONPATH environment variable. In my case, Python is installed to "C:\\Python27". My PYTHONPATH looks like this:

C:\Python27;C:\Python27\DLLs;C:\Python27\Lib

Still, nothing will import. I get errors like this:

File "D:\Code\Django\polls\models.py", line 3, in <module>
    from django.utils import timezone
ImportError: cannot import name timezone

What's wrong with my situation?

Answer 1

Take a look at the official docs on using Python on Windows , in particular the section on finding modules .

You have to add the directory where you installed 3rd party modules to your PYTHONPATH if you didn't install them to your Python27\\Libs\\site-packages directory.

Another option is to get acquainted with pip and virtualenv . These tools make installing 3rd party modules a breeze. Although I don't know how well they are supported on Windows (I mainly do Python development on Linux).

Answer 2

PYTHONPATH = If this variable exists in your environment, Python will add it to the normal search path for modules when you use any import statement; you normally do not modify this as well behaved Python scripts will install themselves in the site-packages directory, and Python searches this by default.

PATH = this is the global file system path. Your operating system will search the directories listed in this variable (from left to right), to find commands when you type something at a command prompt.

In order for Python to work correctly only Windows, the C:\\Python27 directory should be listed in PATH . If you ran the installer as an Administrator, the installer will modify the global PATH and add this for you. If you installed it as a normal user, you need to modify the PATH manually.

To add this manually, right click on My Computer and select Properties . Click on Advanced , then Environment Variables . You'll see two boxes - User Variables and System Variables . You can only edit user variables - system variables need administrative access.

Simply add a new variable (or modify the existing PATH ) You should also add C:\\Python27\\Scripts to your PATH as most commands installed by Python scripts (like django-admin.py) are installed here. Directories are separated by ;

Once you have done this; python should work properly for you on Windows.

Answer 3

virtualenv is good option.
else simply add site-packages in path.