Use __init__.py to modify sys path is a good idea?

Question

I want to ask you something that came to my mind doing some stuff.

I have the following structure:

src
    - __init__.py
    - class1.py
    + folder2
        - __init__.py
        - class2.py

I class2.py I want to import class1 to use it. Obviously, I cannot use

from src.class1 import Class1

cause it will produce an error. A workaround that works to me is to define the following in the __init__.py inside folder2:

import sys
sys.path.append('src')

My question is if this option is valid and a good idea to use or maybe there are better solutions.

Another question. Imagine that the project structure is:

src
    - __init__.py
    - class1.py
    + folder2
        - __init__.py
        - class2.py
    + errorsFolder
        - __init__.py
        - errors.py

In class1:

from errorsFolder.errors import Errors

this works fine. But if I try to do in class2 which is at the same level than errorsFolder:

from src.errorsFolder.errors import Errors

It fails (ImportError: No module named src.errorsFolder.errors)

Thank you in advance!

Answer 1

One correct way to solve this is to set the environment variable PYTHONPATH to the path which contains src. Then import src.class1 will always work, regardless of which directory you start in.