How to make Jupyter notebook use PYTHONPATH in system variables without hacking sys.path directly?

Question

Same problem as in this question sys.path different in Jupyter and Python - how to import own modules in Jupyter?. In pure Python, it prepends my system environment variable

Answer 1

JupyterLab reuses the PYTHONPATH on Linux, so I created a file like

#!/bin/bash
# add your path
export PYTHONPATH="$PYTHONPATH:/opt/your/path"
# start JupyterLab using an environment
/opt/anaconda/envs/MY_ENVIRONMENT/bin/jupyter-lab

saved it as start_my_jupyterlab, make it executeable with chmod a+x start_my_jupyterlab and run it on the shell with start_my_jupyterlab.