∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] {X Y : AlgebraicGeometry.SheafedSpace C} (f : X ⟶ Y)
  [H : AlgebraicGeometry.SheafedSpace.IsOpenImmersion f] (U : TopologicalSpace.Opens ↑↑X.toPresheafedSpace),
  CategoryTheory.IsIso (AlgebraicGeometry.SheafedSpace.IsOpenImmersion.invApp f U)