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

Answer 1

On MacOS, Instead of giving path to a specific library. Giving full path to the root project folder in

~/.bash_profile 

made my day, for example:

export PYTHONPATH="${PYTHONPATH}:/Users/<myuser>/project_root_folder_path"

after this do:

source ~/.bash_profile

Answer 2

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 3

Shortest path between A <-> B is a straight line;

import sys
if not 'NEW_PATH' in sys.path:
  sys.path += ['NEW_PATH']

Answer 4

Fix Python Path issues when you switch from bash to zsh

I ran into Python Path problems when I switched to zsh from bash.

The solution was simple, but I failed to notice.

Pip was showing me, that the scripts blah blah or package blah blah is installed in ~/.local/bin which is not in path.

After reading some solutions to this question, I opened my .zshrc to find that the solution already existed.

I had to simply uncomment a line:

Take a look

Answer 5

Just to add on awesomo's answer, you can also add that line into your ~/.bash_profile or ~/.profile

Answer 6

You could add the path via your pythonrc file, which defaults to ~/.pythonrc on linux. ie.

import sys
sys.path.append('/path/to/dir')

You could also set the PYTHONPATH environment variable, in a global rc file, such ~/.profile on mac or linux, or via Control Panel -> System -> Advanced tab -> Environment Variables on windows.