∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.Abelian C] {X Y : C} (f : X ⟶ Y)
  [inst_2 : CategoryTheory.Epi f] {T : C} (g : X ⟶ T)
  (hg : CategoryTheory.CategoryStruct.comp (CategoryTheory.Limits.kernel.ι f) g = 0),
  CategoryTheory.CategoryStruct.comp f (CategoryTheory.Abelian.epiDesc f g hg) = g