[Bug][Jupyter Widget] Export polygons drawn on the map

**Describe the bug**
Won't say it is a bug, just needed some help

**To Reproduce**
Open any plot and use the tool to draw some polygons. My use case is I am trying to identify some clusters based upon some ecommerce order data.

**Expected behavior**
Need to understand how can i retain those polygons whenever I make the code run again. Right now, they are gone and not saved in the config file or the html

**Screenshots**

**Environment (please complete the following information):**
- Using python3 in google colab
- the version installed by `! pip install -q keplergl`

** Additional **
Is it right now possible to get the details of the points inside the polygon. For example, in the above image if I can get to know the number of points enclosed within the polygon.

Thanks a lot in advance. and for creating such an amazing geo-spatial data vis tool.