Global Variable across modules

I faced this problem while i was expirementing with my project.My project is designed so it has multipule submoudles.

Now each submodule needs a position of an the same item on the screen,which is random each time the program ran.I thought it was a good idea to check once where is the position of the item (It does not change in runtime) , and let all modules access the position.(Since checking the position takes a long time)

This is what i did:

main.py

import Config
import sub_module

main()

def main():
    position = get_pos()
    Config.pos = position
    sub_module.click_on_item()

Config.py

pos = None

I tried using this code , so when i ran the program , it sets the config.py module pos variable , to the position of the item on screen.
This code works fine but when i try to use it in the submodules like this:

sub_module.py

import Config

def click_on_item():
    click(Config.pos)

It resets the value to None , since it reruns the Config module code.
Is there an elegant solution for this problem ? I can't let the position as an argument for the , since my case is much more complex.

One solution that i can think of is writing to the disk , and rereading but it's not fast.

Thanks for the help.

2 EDIT:

My project is multi-package , and there is the problem this is the directory tree:

mainPackage:
    __init__.py
    Config.py
    main.py
    b.py
    Packages:
        Package_A:
            __init__.py
            a.py

main.py

import Config
from Packages.Package_A import a
import b

def main():
    Config.Position = (124, 586)
    a.print_val()
    b.print_val()

if __name__ == '__main__':
    main()

Config

Position = None

b.py

import Config

def print_val():
    print Config.Position

a.py

from mainPackage import Config

def print_val():
    print Config.Position

output

None -> from Package_A
(124, 586) -> from b.py

Sorry for the inconvenience since i didn't know what was causing the problem , my interest is in multi package global variable.