class BaseWithTypeVar<T> {}
    class Outer<O> {
      class Sub<X> extends BaseWithTypeVar<List<X>> {}

      class Sub2<Y extends Sub2<Y>> extends BaseWithTypeVar<List<Y>> {}
    }
    ParameterizedType subtype =
        (ParameterizedType)
            new TypeToken<BaseWithTypeVar<List<?>>>() {}.getSubtype(Outer.Sub.class).getType();
    assertEquals(Outer.Sub.class, subtype.getRawType());

* `dependencies`: to include ✨ router-level dependencies ✨ that apply to all the *path operations* in a router. Up to now, this was only possible with `include_router`.
* `callbacks`: OpenAPI callbacks that apply to all the *path operations* in this router.
* `deprecated`: to mark all the *path operations* in a router as deprecated.