[jupyter] WIP python save_to_json function

[chrisgervang]

• The goal is to export the entire map as a json by calling the following javascript code, and access it from a python function call: const exportedData = state.keplerGl.map.visState.schema.save(state.keplerGl.map)

• Adds a save_to_json python function to compliment the save_to_html function.

This PR is not yet functional. I'm unsure how to implement a low level async data exchange between python->js->python.

Research links: https://ipywidgets.readthedocs.io/en/latest/examples/Widget%20Asynchronous.html#Waiting-for-user-interaction https://ipywidgets.readthedocs.io/en/latest/embedding.html#python-interface https://stackoverflow.com/questions/33845775/send-json-data-to-jupyter-notebook-frontend-via-comm/33846113 https://github.com/jupyter-widgets/ipywidgets/blob/master/docs/source/examples/Widget%20Low%20Level.ipynb https://github.com/jupyter-widgets/ipywidgets/blob/24628f006c8a468994eba7a6e964fe619c992267/ipywidgets/widgets/widget.py#L260 https://github.com/jupyter-widgets/ipywidgets/blob/master/packages/base/src/widget.ts

[heshan0131]

published 2.5.1 with utils in dist

[heshan0131]

what is the goal of the exported json? Loaded back to kepler? then you want to use the getMapJaon method and pass in the entire state. not just visState

[SebastianoX]

Hello! Any news on this MR? Is the save_to_json something still being worked on?