{C : Type u_1} →
  {inst : CategoryTheory.Category.{v_1, u_1} C} →
    {inst_1 : CategoryTheory.Preadditive C} →
      {inst_2 : CategoryTheory.Limits.HasZeroObject C} →
        {inst_3 : CategoryTheory.HasShift C ℤ} →
          {inst_4 : ∀ (n : ℤ), (CategoryTheory.shiftFunctor C n).Additive} →
            {inst_5 : CategoryTheory.Pretriangulated C} →
              {X₁ X₂ X₃ Z₁₂ Z₂₃ Z₁₃ : C} →
                {u₁₂ : X₁ ⟶ X₂} →
                  {u₂₃ : X₂ ⟶ X₃} →
                    {u₁₃ : X₁ ⟶ X₃} →
                      {comm : CategoryTheory.CategoryStruct.comp u₁₂ u₂₃ = u₁₃} →
                        {v₁₂ : Z₁₂ ⟶ X₁} →
                          {w₁₂ : X₂ ⟶ (CategoryTheory.shiftFunctor C 1).obj Z₁₂} →
                            {h₁₂ :
                                CategoryTheory.Pretriangulated.Triangle.mk v₁₂ u₁₂ w₁₂ ∈
                                  CategoryTheory.Pretriangulated.distinguishedTriangles} →
                              {v₂₃ : Z₂₃ ⟶ X₂} →
                                {w₂₃ : X₃ ⟶ (CategoryTheory.shiftFunctor C 1).obj Z₂₃} →
                                  {h₂₃ :
                                      CategoryTheory.Pretriangulated.Triangle.mk v₂₃ u₂₃ w₂₃ ∈
                                        CategoryTheory.Pretriangulated.distinguishedTriangles} →
                                    {v₁₃ : Z₁₃ ⟶ X₁} →
                                      {w₁₃ : X₃ ⟶ (CategoryTheory.shiftFunctor C 1).obj Z₁₃} →
                                        {h₁₃ :
                                            CategoryTheory.Pretriangulated.Triangle.mk v₁₃ u₁₃ w₁₃ ∈
                                              CategoryTheory.Pretriangulated.distinguishedTriangles} →
                                          CategoryTheory.Triangulated.Octahedron' comm h₁₂ h₂₃ h₁₃ → ℕ