Notebook: Can't launch jupyter-lab or jupyter-notebook: AttributeError: type object 'Callable' has no attribute '_abc_registry'

[VitalyAnkh]

I installed jupyter with anaconda, and always keep it up to date. Today I find I can't launch jupyter-lab or jupyter-notebook: python raises an error when I run jupyter-lab with terminal:

Traceback (most recent call last):
File "/opt/anaconda/bin/jupyter-lab", line 7, in
from jupyterlab.labapp import main
File "/opt/anaconda/lib/python3.7/site-packages/jupyterlab/labapp.py", line 12, in
from jupyterlab_server import slugify, WORKSPACE_EXTENSION
File "/opt/anaconda/lib/python3.7/site-packages/jupyterlab_server/__init__.py", line 4, in
from .app import LabServerApp
File "/opt/anaconda/lib/python3.7/site-packages/jupyterlab_server/app.py", line 9, in
from .server import ServerApp
File "/opt/anaconda/lib/python3.7/site-packages/jupyterlab_server/server.py", line 14, in
from notebook.base.handlers import (
File "/opt/anaconda/lib/python3.7/site-packages/notebook/__init__.py", line 25, in
from .nbextensions import install_nbextension
File "/opt/anaconda/lib/python3.7/site-packages/notebook/nbextensions.py", line 610, in
from .extensions import (
File "/opt/anaconda/lib/python3.7/site-packages/notebook/extensions.py", line 8, in
from tornado.log import LogFormatter
File "/opt/anaconda/lib/python3.7/site-packages/tornado/log.py", line 36, in
from tornado.escape import _unicode
File "/opt/anaconda/lib/python3.7/site-packages/tornado/escape.py", line 27, in
from tornado.util import PY3, unicode_type, basestring_type
File "/opt/anaconda/lib/python3.7/site-packages/tornado/util.py", line 48, in
import typing # noqa
File "/opt/anaconda/lib/python3.7/site-packages/typing.py", line 1347, in
class Callable(extra=collections_abc.Callable, metaclass=CallableMeta):
File "/opt/anaconda/lib/python3.7/site-packages/typing.py", line 1003, in __new__
self._abc_registry = extra._abc_registry
AttributeError: type object 'Callable' has no attribute '_abc_registry'

Or this almost the same error when I run jupyter-notebook with terminal:

Traceback (most recent call last):
File "/opt/anaconda/bin/jupyter-notebook", line 7, in
from notebook.notebookapp import main
File "/opt/anaconda/lib/python3.7/site-packages/notebook/__init__.py", line 25, in
from .nbextensions import install_nbextension
File "/opt/anaconda/lib/python3.7/site-packages/notebook/nbextensions.py", line 610, in
from .extensions import (
File "/opt/anaconda/lib/python3.7/site-packages/notebook/extensions.py", line 8, in
from tornado.log import LogFormatter
File "/opt/anaconda/lib/python3.7/site-packages/tornado/log.py", line 36, in
from tornado.escape import _unicode
File "/opt/anaconda/lib/python3.7/site-packages/tornado/escape.py", line 27, in
from tornado.util import PY3, unicode_type, basestring_type
File "/opt/anaconda/lib/python3.7/site-packages/tornado/util.py", line 48, in
import typing # noqa
File "/opt/anaconda/lib/python3.7/site-packages/typing.py", line 1347, in
class Callable(extra=collections_abc.Callable, metaclass=CallableMeta):
File "/opt/anaconda/lib/python3.7/site-packages/typing.py", line 1003, in __new__
self._abc_registry = extra._abc_registry
AttributeError: type object 'Callable' has no attribute '_abc_registry'

How to fix it?

[dave-wilkins]

I found the same issue.
My crude workaround - drop back to Python 3.6.
When I installed Keras, it downgraded a significant number of modules to prior versions including Python to 3.6.

I later created a new environment py37 and upgraded Python to 3.7 in that environment.
Activated py37 tried to launch jupyter notebook and once again got the error. I'm running on a Mac, have yet to check it out on my virtual windows install.

[dave-wilkins]

Later, I used anaconda-clean then trashed anaconda, re-installed (getting python 3.7).

Could not launch jupyter notebook from Terminal, nor from Anaconda navigator without getting "Callable has n attribute _abc_registry". But I could launch jupyter-lab from Anaconda navigator, then used Help menu to display lab as jupyter notebook.

It's a workaround that got jupyter notebook running nicely.

[pradeepcheers]

This is because typing library is in the standard library since 3.5. If you have older version of typing uninstalling it does the trick

sudo pip3 uninstall typing

[VitalyAnkh]

@dave-wilkins @pradeepcheers Thanks to your help, this problem has been fixed!