Serving react web page from a flask web server

See more:

Python

Node.js

React

flask

There may be a better way to do this, please let me know if there is.

We have an API served by a Flask web server; this can't be changed.
We have web client - SPA using react providing dynamic content served by the API.
We want to deploy this all via Elastic Beanstalk in AWS.

What I really want to do is use the flask server to serve the client pages - html/js/css/etc.

I'm going round in circles trying to find examples or ideas.

So, any ideas how to do this or half-sane terms to search for; my google foo is weak on this.

What I have tried:

I tried copying the client into the static part of the flask app.
I can run two web servers - Flask for the api, node.js for the client - but I want them together.