Jupyterlab and tqdm_notebook

The following code errors out with, ```NameError: name 'IntProgress' is not defined```

```
import tqdm
tqdm.tqdm_notebook().pandas()
df.progress_apply(func, axis=1)
```
I imported ```ipywidgets.IntProgress``` with no luck.

Python=3.6
Jupyter=4.2.1 
Jupyter lab=0.18.1