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Created Jun 24, 2015

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root@Debian-70-wheezy-64-minimal:~# jupyterhub-singleuser
Traceback (most recent call last):
File "/home/epinux/dev/ipython/src/traitlets/traitlets/", line 432, in __get__
value = obj._trait_values[]
KeyError: None
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/epilib/Envs/env1/bin/jupyterhub-singleuser", line 4, in <module>
File "/home/epilib/Envs/env1/lib/python3.4/site-packages/jupyterhub/", line 221, in main
return SingleUserNotebookApp.launch_instance()
File "/home/epilib/Envs/env1/lib/python3.4/site-packages/IPython/config/", line 573, in launch_instance
File "<string>", line 2, in initialize
File "/home/epilib/Envs/env1/lib/python3.4/site-packages/IPython/config/", line 75, in catch_config_error
return method(app, *args, **kwargs)
File "/home/epilib/Envs/env1/lib/python3.4/site-packages/IPython/html/", line 1015, in initialize
File "/home/epilib/Envs/env1/lib/python3.4/site-packages/jupyterhub/", line 191, in init_webapp
s['user'] = self.user
File "/home/epinux/dev/ipython/src/traitlets/traitlets/", line 438, in __get__
% (, obj))
traitlets.traitlets.TraitError: No default value found for None trait of <jupyterhub.singleuser.SingleUserNotebookApp object at 0x7fdc5ae37fd0>
If you suspect this is an IPython bug, please report it at:
or send an email to the mailing list at
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:
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