∀ (C : Type u_1) [inst : CategoryTheory.Category.{v_1, u_1} C] [inst_1 : CategoryTheory.HasShift C ℤ]
  (X : CategoryTheory.Pretriangulated.Triangle Cᵒᵖ),
  ((CategoryTheory.Pretriangulated.TriangleOpEquivalence.counitIso C).inv.app X).hom₁ =
    CategoryTheory.CategoryStruct.id X.obj₁