[Tutor] sibling import

[Mats Wichmann]

On 10/12/2017 05:15 AM, Atar new wrote:
> Hi Team,
> 
> Here is my problem. I want to use sibling import but it is not working . I
> know taht if we add the directory in sys.path ,it will work.
> 
> But I have to package the whole application and will create a setup.py file
> out of it .
> What is the standard way to do it?
> 
> 
>    1. mkdir A
>    2. mkdir B
>    3.
>    4. touch A/__init__.py
>    5. touch B/__init__.py
>    6.
>    7. touch A/foo.py
>    8. touch B/bar.py
>    9.
>    10. cat B/bar.py
>    11. from A import foo
>    12.
>    13.
>    14. python B/bar.py
>    15. ImportError: No module named A
> 
> 
> 
> Thanks
> Anju

This isn't the way: from the context of bar.py in B, there is no A.  You
generally speaking want a relative import (from .A import foo) for
modern python versions, but because of the path structure you've set up,
even that won't work, the script doing the importing would need to be in
the top directory of your package. "Sibling" imports just don't work
well.  There was a PEP somewhere about this, which as I recall required
some horrid looking hack.

So with a bit of hunting,
https://www.python.org/dev/peps/pep-0366
and more reading at
https://www.python.org/dev/peps/pep-0338