How to solve "no module named" problem for Python when using Environment Modules package?

Question

I am using a software environment loaded with the Environment Modules package (not to be confused with Python modules) using module load my_env. Within this environment, I am attempting to run a python script that imports a self-defined Python module using import my_py_module. When I tried to run this script, an error is reported saying

ModuleNotFoundError: No module named 'my_py_module'

How can I solve this issue?

Answer 1

The my_env modulefile should update the PYTHONPATH environment variable to add the location of the my_py_module.

$ cat /path/to/modulefiles/my_env
#%Module
append-path PYTHONPATH /path/to/my_py_module/location

Once such modulefile is loaded, you should be able to run a python script that imports my_py_module:

$ module use /path/to/modulefiles
$ module load my_env
$ python myscript.py