If you get an error saying something like ‘Can not import SomeModule”, the first thing to check is that package (which is a regular directory with added __init__.py file) is in PYTHONPATH.
For example, suppose you get an error when executing
from util import SafeMath
I would open python shell to check if its in PYTHONPATH and then to see which modules/files are seen by interpreter in case of potential name conflicts:
The above will display all directories in PYTHONPATH.
The above will display all files/modules found in the package