code: def read_main(request: Request):
      return {
          "message": "Hello World",
          "root_path": request.scope.get("root_path"),
      }
  
imports: from fastapi import FastAPI, Request
  from fastapi.testclient import TestClient
label_desc: Use image node_id 1 for calling a global function with example usage: read_main(request) and returns: dict