Permanently add a directory to PYTHONPATH?

Question

Whenever I use sys.path.append, the new directory will be added. However, once I close python, the list will revert to the previous (default?) values. How do I permanently add a directory to PYTHONPATH?

Answer 1

If you're using bash (on a Mac or GNU/Linux distro), add this to your ~/.bashrc

export PYTHONPATH="${PYTHONPATH}:/my/other/path"

Answer 2

For me it worked when I changed the .bash_profile file. Just changing .bashrc file worked only till I restarted the shell.

For python 2.7 it should look like:

export PYTHONPATH="$PYTHONPATH:/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python"

at the end of the .bash_profile file.

Answer 3

I added permanently in Windows Vista, Python 3.5

System > Control Panel > Advanced system settings > Advanced (tap) Environment Variables > System variables > (if you don't see PYTHONPATH in Variable column) (click) New > Variable name: PYTHONPATH > Variable value:

Please, write the directory in the Variable value. It is details of Blue Peppers' answer.

Answer 4

You need to add your new directory to the environment variable PYTHONPATH, separated by a colon from previous contents thereof. In any form of Unix, you can do that in a startup script appropriate to whatever shell you're using (.profile or whatever, depending on your favorite shell) with a command which, again, depends on the shell in question; in Windows, you can do it through the system GUI for the purpose.

superuser.com may be a better place to ask further, i.e. for more details if you need specifics about how to enrich an environment variable in your chosen platform and shell, since it's not really a programming question per se.

Answer 5

Adding export PYTHONPATH="${PYTHONPATH}:/my/other/path" to the ~/.bashrc might not work if PYTHONPATH does not currently exist (because of the :).

export PYTHONPATH="/my/other/path1"
export PYTHONPATH="${PYTHONPATH}:/my/other/path2"

Adding the above to my ~/.bashrc did the trick for me on Ubuntu 16.04

Answer 6

This works on Windows

1. On Windows, with Python 2.7 go to the Python setup folder.
2. Open Lib/site-packages.
3. Add an example.pth empty file to this folder.
4. Add the required path to the file, one per each line.

Then you'll be able to see all modules within those paths from your scripts.