I'm a newbie to Python and iOS programming so use my advice at your own risk.
If you've jailbroken your phone and have installed iFile (search for it on Cydia), you can do two things that were crucial to me.
- Create symbolic links
If you create symbolic links, you can place the link inside the Pythonista sandbox and it will point elsewhere in the filesystem. These symbolic links will remain even after you restore a phone to its non jailbroken state.
- Change user priveleges for certain files.
I'm working on a jailbroken app that consolidates messages across multiple media. When jailbroken, I can access the sandboxes of other apps, but accessing the iOS AddressBook.db and sms.db is trickier. Using iFile, I changed the privileges on those files to "Read, Write, Execute" for everybody. Problem solved.