NotImplemented Error Jupyter Notebook

[SajjanKarn]

i had currently install jupyter notebook for python3.8 by using this command
pip install jupyter

everything looks fine but when i try to open notebook via jupyter notebook
it gives me this error,

Traceback (most recent call last):
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.240.0_x64__qbz5n2kfra8p0\lib\runpy.py", line 192, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.240.0_x64__qbz5n2kfra8p0\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\97798\Desktop\wEB PROJECTS\testenv\Scripts\jupyter-notebook.EXE\__main__.py", line 9, in <module>
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\jupyter_core\application.py", line 268, in launch_instance
    return super(JupyterApp, cls).launch_instance(argv=argv, **kwargs)
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\traitlets\config\application.py", line 663, in launch_instance
    app.initialize(argv)
  File "<c:\users\97798\desktop\web projects\testenv\lib\site-packages\decorator.py:decorator-gen-7>", line 2, in initialize
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\traitlets\config\application.py", line 87, in catch_config_error
    return method(app, *args, **kwargs)
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\notebook\notebookapp.py", line 1720, in initialize
    self.init_webapp()
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\notebook\notebookapp.py", line 1482, in init_webapp
    self.http_server.listen(port, self.ip)
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\tornado\tcpserver.py", line 152, in listen
    self.add_sockets(sockets)
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\tornado\tcpserver.py", line 165, in add_sockets
    self._handlers[sock.fileno()] = add_accept_handler(
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\tornado\netutil.py", line 279, in add_accept_handler
    io_loop.add_handler(sock, accept_handler, IOLoop.READ)
  File "c:\users\97798\desktop\web projects\testenv\lib\site-packages\tornado\platform\asyncio.py", line 99, in add_handler
    self.asyncio_loop.add_reader(fd, self._handle_events, fd, IOLoop.READ)
  File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.240.0_x64__qbz5n2kfra8p0\lib\asyncio\events.py", line 501, in add_reader
    raise NotImplementedError
NotImplementedError


please help me

[KingDarBoja]

This issue has been addressed on #5047.

It provides a workaround on the meantime for existing releases.

Cheers!

[SajjanKarn]

Fixed by adding this code

import sys

if sys.platform == 'win32':
    import asyncio
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

in python38/Lib/site-packages/tornado/platorm/asyncio.py after the main method.

[vipulmahiman]

great, thanks. It worked.

[animedhruv]

it isn't working for me can you please help

[softtechnoes]

Fixed by adding this code

import sys

if sys.platform == 'win32':
    import asyncio
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

in python38/Lib/site-packages/tornado/platorm/asyncio.py after the main method.

that's working but correct the path of the file, below is correct one

in python38/Lib/site-packages/tornado/platform/asyncio.py after the main method.

[raghuvamsicoding]

Fixed by adding this code

import sys

if sys.platform == 'win32':
    import asyncio
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

in python38/Lib/site-packages/tornado/platorm/asyncio.py after the main method.

Worked. Thank you!

[Artem0nster]

Thx man, it worked!

[adityadubey1996]

thanks bro, it worked

[LintangWisesa]

Fixed by adding this code

import sys

if sys.platform == 'win32':
    import asyncio
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

in python38/Lib/site-packages/tornado/platorm/asyncio.py after the main method.

Thanks @SajjanKarn, this is the best solution for Python 3.8. 3 People already saved by yours.

[kevin-bates]

Right on - glad to see success with this. For the benefit of others and now that notebook 6.0.3 is available, this issue can be addressed by upgrading notebook.

pip install notebook --upgrade

or, for conda envs,

conda update -c conda-forge notebook

[Tao-Lu]

Right on - glad to see success with this. For the benefit of others and now that notebook 6.0.3 is available, this issue can be addressed by upgrading notebook.

pip install notebook --upgrade

or, for conda envs,

conda update -c conda-forge notebook

worked for me, thanks

[efelex]

for windows this is in
C:\Users\hp\AppData\Local\Programs\Python\Python38\Lib\site-packages\tornado\platform