Python3 import module from sibling directory

Question

For a new structure in the python 3.10 project I had to separate diffrent modules from each other and moved them in diffrent folders on the same layer. The folder stucture looks kinda similar to this:

Root
-- main.py
-- __init__.py

-- folder1
----- __init__.py
----- a.py

-- folder2
----- __init__.py
----- b.py

I defined a function in a.py like this:

# /root/folder1/a.py
def testFunction(text):
    print(text)

In the Root init file i referenced this function like so:

# /root/__init__.py
from .folder1.a import testFunction as testFunction

So I tried to use the function in module folder1/a.py in module folder2/b.py:

# /root/folder2/b.py
from .. import testFunction
text = 'hello World'
testFunction(text)

I searched on GitHub for a bigger python projects and found the solution on top for module references but it didn't worked for me. I tried following solutions which also didn't worked:

• https://www.geeksforgeeks.org/python-import-from-sibling-directory/?ref=lbp
• https://itsmycode.com/importerror-attempted-relative-import-with-no-known-parent-package/
• https://iq-inc.com/importerror-attempted-relative-import/

So my problem is, that this Error shows up:

ImportError: attempted relative import with no known parent package

thank you verry much for every hint or solution :-)

Answer 1

I found out, that I could work with sys.path.append & os.path.abspath. So the solution is like this:

directory stucture:

Root
-- main.py
-- __init__.py

-- folder1
----- __init__.py
----- a.py

-- folder2
----- __init__.py
----- b.py

To use testFunction from folder1/a.py in folder2/b.py the code in b.py should be like this:

import sys
import os

sys.path.append(os.path.abspath('../Root/folder1'))
from a import testFunction