django save a form for a user that has not registered yet
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I need some advice / ideas if someone is inclined to help: I have a javascript interface for manipulating pictures. Basically it's about moving photos around. Once it's done the position of images is saved into a Django form and then saved to database with the owner saved as the current user. Now the trick is that I would like to be able to allow non registered users to play with this interface and then if they like the result they hit save and are redirected to an account registration page and only then the form is actually saved with their user as the owner.

What comes to my mind now is to keep the values of the form in session but I don't know what will happen to the session once the anonymous user registers and becomes another user. I was also thinking of using a 'next' parameter in the registration process with the url filled with get parameters that would be the content of the form but then I don't know if userena is ready to allow that.
Any light on this is welcome.