code: def test_spec_attribute(app):
      spec = app._get_spec()
  
      @app.route("/foo")
      @app.output(Foo)
      def foo():
          pass
  
      assert "/foo" not in spec["paths"]
      assert "/foo" in app.spec["paths"]
  
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 8 for calling a global function with example usage: test_spec_attribute(app) without return types