∀ {C : Type u_1} [inst : CategoryTheory.Category.{v_1, u_1} C] [inst_1 : CategoryTheory.Limits.HasZeroMorphisms C]
  {Z : CategoryTheory.Functor (CategoryTheory.ShortComplex C) C} (h : CategoryTheory.ShortComplex.π₃ ⟶ Z),
  CategoryTheory.CategoryStruct.comp CategoryTheory.ShortComplex.π₁Toπ₂
      (CategoryTheory.CategoryStruct.comp CategoryTheory.ShortComplex.π₂Toπ₃ h) =
    CategoryTheory.CategoryStruct.comp 0 h