ipcluster nbextension enable
Enabling IPython clusters tab
Traceback (most recent call last):
  File "/srv/paws/bin/ipcluster", line 11, in <module>
    sys.exit(launch_new_instance())
  File "/srv/paws/lib/python3.6/site-packages/traitlets/config/application.py", line 658, in launch_instance
    app.start()
  File "/srv/paws/lib/python3.6/site-packages/ipyparallel/apps/ipclusterapp.py", line 641, in start
    return self.subapp.start()
  File "/srv/paws/lib/python3.6/site-packages/ipyparallel/apps/ipclusterapp.py", line 604, in start
    install_extensions(enable=True, user=self.user)
  File "/srv/paws/lib/python3.6/site-packages/ipyparallel/nbextension/install.py", line 24, in install_extensions
    toggle_serverextension_python('ipyparallel.nbextension', user=user)
  File "/srv/paws/lib/python3.6/site-packages/notebook/serverextensions.py", line 74, in toggle_serverextension_python
    cm.update("jupyter_notebook_config", cfg)
  File "/srv/paws/lib/python3.6/site-packages/traitlets/config/manager.py", line 87, in update
    self.set(section_name, data)
  File "/srv/paws/lib/python3.6/site-packages/traitlets/config/manager.py", line 71, in set
    self.ensure_config_dir_exists()
  File "/srv/paws/lib/python3.6/site-packages/traitlets/config/manager.py", line 46, in ensure_config_dir_exists
    os.makedirs(self.config_dir, 0o755)
  File "/usr/lib/python3.6/os.py", line 220, in makedirs
    mkdir(name, mode)
PermissionError: [Errno 13] Permission denied: '/usr/local/etc/jupyter'

If you suspect this is an IPython bug, please report it at:
    https://github.com/ipython/ipython/issues
or send an email to the mailing list at ipython-dev@python.org

You can print a more detailed traceback right now with "%tb", or use "%debug"
to interactively debug it.

Extra-detailed tracebacks for bug-reporting purposes can be enabled via:
    c.Application.verbose_crash=True