∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.Limits.HasZeroMorphisms C]
  (X : CategoryTheory.ShortComplex C),
  CategoryTheory.Arrow.homMk (CategoryTheory.CategoryStruct.id X).τ₁ (CategoryTheory.CategoryStruct.id X).τ₂ ⋯ =
    CategoryTheory.CategoryStruct.id (CategoryTheory.Arrow.mk X.f)