code: def test_spec(app):
      assert app.spec
      assert "openapi" in app.spec
  
imports: import json
  import pytest
  from flask import request
  from openapi_spec_validator import validate_spec
  from .schemas import Bar
  from .schemas import Baz
  from .schemas import Foo
  from apiflask import APIBlueprint
  from apiflask import Schema
  from apiflask.commands import spec_command
  from apiflask.fields import Integer
label_desc: Use image node_id 1 for calling a global function with example usage: test_spec(app) without return types