Can't access programming assignments

Sorry, but that’s the way the courses work here: when you finish, they disable your access. So the right thing to do was to download the assignments once you finish them while you are still actively taking the course. This is documented on the DLS FAQ Thread on this topic.

Your only alternative at this point is to do as Kic suggests and see if the Coursera Help folks will be nice to you. No guarantees, though …