This package provides a Jupyter notebook cell magic %%notify that notifies the user upon completion of a potentially long-running cell via a browser push notification. Use cases include long-running machine learning models, grid searches, or Spark computations. This magic allows you to navigate away to other work (or even another Mac desktop entirely) and still get a notification when your cell completes. Clicking on the body of the notification will bring you directly to the browser window and tab with the notebook, even if you're on a different desktop (clicking the "Close" button in the notification will keep you where you are). The extension has currently been tested in Chrome (Version: 58.0.3029) and Firefox (Version: 53.0.3).