jupyter install nbextentions

install using pip

pip install jupyter_contrib_nbextensions

jupyter contrib nbextension install --user

pip install jupyter_nbextensions_configurator

jupyter nbextensions_configurator enable --user

If that fails, you can use conda to install

conda install -c conda-forge jupyter_nbextensions_configurator
conda install -c conda-forge jupyter_contrib_nbextensions
jupyter contrib nbextension install --user
jupyter nbextensions_configurator enable --user

After restarting the notebook, there is a new column on the interface, as shown below:

The favorite is code folding codefolding, you can check to enable it, or you can use code to enable (enable)/disable (disable)

jupyter nbextension enable codefolding/main

The effect is as follows:

 

References:

https://github.com/ipython-contrib/jupyter_contrib_nbextensionshttps://github.com/ipython-contrib/jupyter_contrib_nbextensions