## Plotly in a virtual environment displaying in JupyterLab.

Install these first...

```
pip install ipywidgets
pip install jupyter-dash
```

If you try Plotly in a virtual environment you might only see a blank area...

```python
import plotly.express as px
df = px.data.gapminder().query("country=='Canada'")
fig = px.line(df, x="year", y="lifeExp", title='Life expectancy in Canada', template="plotly_dark")
fig.show()
```

If you list the extensions, you'll probably find that the Plotly extension isn't installed...

```cmd
Microsoft Windows [Version 10.0.19044.2130]
(c) Microsoft Corporation. All rights reserved.

C:\Users\J2897>jupyter labextension list
JupyterLab v3.4.8
C:\Users\J2897\AppData\Local\Programs\Python\Python39\share\jupyter\labextensions
        jupyterlab_pygments v0.2.2 enabled ok (python, jupyterlab_pygments)


C:\Users\J2897>
```

The command to install it is mentioned on the [Plotly site](https://plotly.com/python/troubleshooting/#jupyterlab-problems)...

```cmd
Microsoft Windows [Version 10.0.19044.2130]
(c) Microsoft Corporation. All rights reserved.

C:\Users\J2897>jupyter labextension install @jupyter-widgets/jupyterlab-manager jupyterlab-plotly
Building jupyterlab assets (production, minimized)
\
C:\Users\J2897>jupyter labextension list
JupyterLab v3.4.8
C:\Users\J2897\AppData\Local\Programs\Python\Python39\share\jupyter\labextensions
        jupyterlab_pygments v0.2.2 enabled ok (python, jupyterlab_pygments)

Other labextensions (built into JupyterLab)
   app dir: C:\Users\J2897\AppData\Local\Programs\Python\Python39\share\jupyter\lab
        @jupyter-widgets/jupyterlab-manager v5.0.3 enabled ok
        jupyterlab-plotly v5.10.0 enabled ok


C:\Users\J2897>
```