Dealing with Python's ModuleNotFoundError (I'd appreciate any advice if there's a better way)

Set PYTHONPATH in the environment variable

export PYTHONPATH="Absolute path one level higher than the module in error"

You should not get ** ModuleNotFoundError ** in the process where you entered the above command.

How to check if you can enter in PYTHON PATH properly

Launch python's interactive mode in the same process

>>> import sys
>>> print(sys.path)
['', 'Absolute path one level higher than the module in error','../../site-packages',...]

If it looks like the above, ** ModuleNotFoundError ** should be resolved. It feels better than embedding sys.path.append ("the absolute path one level above the module in error"). If anyone knows a better way, I would appreciate it if you could let me know. If you find something that feels good, I'll put it together.