Have a good talk with your tutor, and say that you are only going out for an internship for a period of time, and it is a directional internship. When you come back, you can do projects better and write papers more smoothly. In short, all you have to do is say that the internship is very helpful to you. If this still doesn't work, it's not good to have a conflict with the tutor, because the tutor has great power. If you are stuck, it is foolish to postpone graduation. You'd better wait until graduation before you go to work.