sage -n jupyter file_name.ipynb

Please wait while the Sage Jupyter Notebook server starts...
[I 17:13:58.979 NotebookApp] Using MathJax: nbextensions/mathjax/MathJax.js
[I 17:13:59.177 NotebookApp] Serving notebooks from local directory: /home/eric/sage/8.7.develop
[I 17:13:59.177 NotebookApp] The Jupyter Notebook is running at:
[I 17:13:59.177 NotebookApp] http://localhost:8888/?token=fe7a048559fa30b3f0a47ca93f6974e4f658a98976e94f7f
[I 17:13:59.177 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
Traceback (most recent call last):
  File "/home/eric/sage/8.7.develop/src/bin/sage-notebook", line 267, in <module>
    launcher(unknown)
  File "/home/eric/sage/8.7.develop/src/bin/sage-notebook", line 99, in __init__
    main(argv)
  File "/home/eric/sage/8.7.develop/local/lib/python2.7/site-packages/jupyter_core/application.py", line 266, in launch_instance
    return super(JupyterApp, cls).launch_instance(argv=argv, **kwargs)
  File "/home/eric/sage/8.7.develop/local/lib/python2.7/site-packages/traitlets/config/application.py", line 658, in launch_instance
    app.start()
  File "/home/eric/sage/8.7.develop/local/lib/python2.7/site-packages/notebook/notebookapp.py", line 1784, in start
    self.launch_browser()
  File "/home/eric/sage/8.7.develop/local/lib/python2.7/site-packages/notebook/notebookapp.py", line 1742, in launch_browser
    with open(fd, 'w', encoding='utf-8') as fh:
TypeError: coercing to Unicode: need string or buffer, int found