∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] [inst_1 : CategoryTheory.Abelian C]
  (S : CategoryTheory.ShortComplex C) {cg : CategoryTheory.Limits.KernelFork S.g}
  (hg : CategoryTheory.Limits.IsLimit cg) {cf : CategoryTheory.Limits.CokernelCofork S.f}
  (hf : CategoryTheory.Limits.IsColimit cf),
  S.Exact ↔ CategoryTheory.CategoryStruct.comp (CategoryTheory.Limits.Fork.ι cg) (CategoryTheory.Limits.Cofork.π cf) = 0