∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.HasShift C ℤ] {J : Type u_1}
  (T : J → CategoryTheory.Pretriangulated.Triangle C) [inst_2 : CategoryTheory.Limits.HasProduct fun j => (T j).obj₁]
  [inst_3 : CategoryTheory.Limits.HasProduct fun j => (T j).obj₂]
  [inst_4 : CategoryTheory.Limits.HasProduct fun j => (T j).obj₃]
  [inst_5 : CategoryTheory.Limits.HasProduct fun j => (CategoryTheory.shiftFunctor C 1).obj (T j).obj₁] (j : J),
  (CategoryTheory.Pretriangulated.productTriangle.π T j).hom₃ = CategoryTheory.Limits.Pi.π (fun j => (T j).obj₃) j