Port a Python application from Visual Studio to Ubuntu 22.0 running an Eclipse IDE with its PyDev extension

Question

The Visual Studio app has the following tree structure:

MCTS
  |------dlgo
  |        |-----encoders folder
  |        |-----some .py files
  |
  |------generate_mcts_games.py

import numpy as np
from dlgo.encoders import get_encoders_by_name
           ...
if __name__ == '__main__':
       main()

Following the PyDev manual, I have built the following structure under Ubuntu:

  MCTS
   |----------src
   |           |------root
   |                   |-----nested
   |                   |        |-----__init__.py
   |                   |        |-----generate_mcts_games.py
   |                   |-----__init__.py
   |---python (/usr/local/bin/python)  

When I run the app, it starts correctly, but as I did not add the dlgo folder it sends a message 'no module named dlgo'.

All my tentatives to place the dlgo folder have been unsuccessful, with always the same problem to find the dlgo module;
Here are my questions:

1 What is nested?
   Is it dedicated to java?
   Should it be used with Python?
 2 Where should I place the dlgo directory?
 3 Should dlgo be added as a folder or a package?
   I read somewhere that if it is a package, its address location will be put in PYTHONPATH