Answers for "from . import ( ImportError: cannot import name 'constants' from partially initialized module 'zmq.backend.cython' (most likely due to a circular import) (C:\Users\HP\AppData\Roaming\Python\Python38\site-packages\zmq\backend\cython\__init__.py)"

from . import ( ImportError: cannot import name 'constants' from partially initialized module 'zmq.backend.cython' (most likely due to a circular import) (C:\Users\HP\AppData\Roaming\Python\Python38\site-packages\zmq\backend\cython\__init__.py)

pip uninstall pyzmq
pip install pyzmq

The thing with conda is that it has a lot of conflicts, you might be having a conflict. Using simple pip command would help you to remove those conflicts. I mean it worked for me. I hope it helps
# refrence taken from github issues click here for more-> https://github.com/jupyter/notebook/issues/3435