Q:

python import module multi-levels

I'm using Flask framework and would like to test a single class (not Flask app, and I've read the test documentation here)
My folder structure is like below picture, and init.py for each folder.

But I tried all below but none of them works.
from ... import grouper

or
import reporting.dashboard.helpers.grouper

or
import dashboard
from dashboard.helpers.grouper import Grouper

Could anyone please give me some hints on how to include

reporting/dashboard/helpers/grouper.py

in my test module located at 

reporting/tests/helpers/helper-test.py

?
Thanks a lot.

A:

I've identified the cause. It's because the __init__.py under folder "reporting" is not empty, but doing some initiation operations for Flask app. When I made this "__init__.py" a empty file, the import was successful using
from reporting.dashboard.helpers.grouper import Grouper

Also, python-2.6 may not recognize "from xxx import yyyClass", but only "import xxxModule"
reference reading: 
The import system

