What's causing this issue with 2/3 module compatibility in python? -

i have directory structure this:

> coolmod -> __init__.py -> coolmod.py 

in __init__.py have:

from coolmod import * 

i have directory of unittests, run fine in both python 2 , 3. however, when go above directory containing coolmod __init__.py command run in python 2. in python 3, attributeerror: module 'coolmod' has no attribute 'coolfunc'. changed , have achieve desired result?