∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] {J : CategoryTheory.GrothendieckTopology C} {D : Type u_1}
  [inst_1 : CategoryTheory.Category.{v_1, u_1} D] [inst_2 : CategoryTheory.HasWeakSheafify J D]
  (P : CategoryTheory.Sheaf J D), CategoryTheory.IsIso ((CategoryTheory.sheafificationAdjunction J D).counit.app P).hom