code: def test_schema():
      response = client.get("/openapi.json")
      assert response.status_code == status.HTTP_200_OK
      actual_schema = response.json()
      assert actual_schema == expected_schema
  
file_path: fastapi/tests/test_enforce_once_required_parameter.py
imports: from typing import Optional
  from fastapi import Depends, FastAPI, Query, status
  from fastapi.testclient import TestClient
label_desc: Use image node_id 4 for calling a global function with example usage: test_schema() without return types