I spent awhile figuring out how to do this and thought I could share with you.
I made a Gist on how to export the session details (key, secret, screenname) which was saved using TwitterKit. Note that this is only tested with TwitterKit pre-open-source, so if you are using the latest open-sourced TwitterKit, YMMV.
Also note that it just exports the first found session, then deletes all of it from the keychain - you have to save those details somewhere else…
