Error installing Jupyter widget

[wrcannon]

I installed nodeJS but regardless when I execute
jupyter labextension install @jupyter-widgets/jupyterlab-manager
I get the error message
$ jupyter labextension install @jupyter-widgets/jupyterlab-manager
An error occured.
ValueError: Please install nodejs 5+ and npm before continuing installation. nodejs may be installed using conda or directly from the nodejs website.
See the log file for details: /var/folders/95/3w0p4b7x1_s4f90mckw29mmx4mgh2r/T/jupyterlab-debug-ugc3uv_h.log

The log file contains:
NodeJS was not found. Yarn user configuration is ignored.
Traceback (most recent call last):

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/debuglog.py", line 47, in debug_logging
yield

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/labextensions.py", line 93, in start
ans = self.run_task()

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/labextensions.py", line 149, in run_task
for i, arg in enumerate(self.extra_args)

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/labextensions.py", line 149, in
for i, arg in enumerate(self.extra_args)

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/commands.py", line 396, in install_extension
_node_check(app_options.logger)

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab/commands.py", line 1754, in _node_check
node = which('node')

File "/Users/d3k137/.pyenv/versions/anaconda3-2020.02/lib/python3.7/site-packages/jupyterlab_server/process.py", line 59, in which
raise ValueError(msg)

ValueError: Please install nodejs 5+ and npm before continuing installation. nodejs may be installed using conda or directly from the nodejs website.

Exiting application: jupyter

---

$ jupyter --version
jupyter core : 4.6.1
jupyter-notebook : 6.0.3
qtconsole : 4.6.0
ipython : 7.12.0
ipykernel : 5.1.4
jupyter client : 5.3.4
jupyter lab : 1.2.6
nbconvert : 5.6.1
ipywidgets : 7.5.1
nbformat : 5.0.4
traitlets : 4.3.3