Create and activate a virtual environment:

$ python -m venv ./venv
$ source venv/bin/activate

Install dependencies into your active environment:

(venv)$ python -m pip install -U pip jupyterlab ipywidgets matplotlib
(venv)$ python -m jupyter labextension install @jupyter-widgets/jupyterlab-manager

Start Jupter Lab in the same directory where the examples are located:

(venv)$ python -m jupyterlab