This CosmosAIGraph reference implementation is entirely written in Python3 and all microservices utilize the FastAPI web framework.
FastAPI is a modern and asynchronous web framework, and is seen as the successor to Flask. It is also greatly simpler than the Django web framework, which is oriented toward RDBMS-backed web applications.
With FastAPI, you can leverage the Pydantic library to define your endpoint requests and responses as Pydantic Models as described here: https://fastapi.tiangolo.com/tutorial/body-nested-models/
This can enable automatic generation of OpenAPI/Swagger documentation that is useful to the producers and consumers of your microservices.
You can invoke the FastAPI-created /docs endpoint to see the generated documentation. An example is shown in the screen shot below.
This functionality can be disabled as described here: https://fastapi.tiangolo.com/tutorial/metadata/#docs-urls