Invoke Api Gateway Websockets API through HTTP

AWS provides us an SDK way to interact with WebSocket APIs, post_to_connection, delete_connection, get_connection

But how can we invoke the APIs from HTTP, which means a kind of python requests thing?

What I tried?

• AWS Doc: How to call Websocket Connections

Here I'm struggling to find an example for how to sign a req开发者_运维技巧uest for an API Gateway service.