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Python -- Importing Modules

Hi! I'm just wondering a bit here. With importing modules in Python, I usually go about it like this when I'm using standard modules:

Code:

#Standard module

import os

#No problems at runtime

But when I'm creating my own application, the directory structure might look a bit like this:

Code:

~$ Fighting Game/

    __init__.py

    dir1/

        script1a.py

        script1b.py

        __init__.py

    dir2/

        script2a.py

        script2b.py

        __init__.py

There's no problem doing this is script1a:

Code:

import script1b

But in doing this:

Code:

import script2a

An ImportError occurs and it claims it does not exist. I've attempted relative importing, but it doesn't seem to work even with:

Code:

import ..script2b

Is there a better way than adding the package in development, to my PYTHONPATH? I'd like to simply refer to the different modules in the different directories rather than go forth with just putting everything into the system itself.

Any help with this?

If import accepts pathnames, then use proper pathnames:

Code:

bad: import ..script2b

good:import ../dir2/script2b

Code:

script2a = __import__('dir2.script2a',level=1)

Kevin Barry

The way I usually do this is with a .pth file and the site module.

dir1/deps.pth

Code:

../dir2

dir1/script1a.py

Code:

import site

site.addsitedir('.') # picks up the paths in dir1/deps.pth

You can use relative or absolute paths in both the .pth file and addsitedir() call. The path information can live in version control and you don't have to mess with environment variables. The way I usually arrange things is to have a deps.pth in the top level and the addsitedir() in any scripts that are expected to be __main__. addsitedir() does little more than adding paths to sys.path, so if the top level script does it, all the imported modules will see the paths too.

As a bonus, you can make this work with pylint so that it finds all of your local dependencies.

.pylintrc

Code:

[MASTER]

init-hook=import site; site.addsitedir('.')