∀ {C : Type u_1} {D : Type u_2} [inst : CategoryTheory.Category.{v_1, u_1} C]
  [inst_1 : CategoryTheory.Category.{v_2, u_2} D] [inst_2 : CategoryTheory.Preadditive C]
  [inst_3 : CategoryTheory.Preadditive D] (F : CategoryTheory.Functor C D) [inst_4 : F.Additive],
  (CategoryTheory.AdditiveFunctor.of F).obj = F