{C₁ : Type u_1} →
  {C₂ : Type u_2} →
    {C₃ : Type u_3} →
      {C₄ : Type u_4} →
        {inst : CategoryTheory.Category.{v_1, u_1} C₁} →
          {inst_1 : CategoryTheory.Category.{v_2, u_2} C₂} →
            {inst_2 : CategoryTheory.Category.{v_3, u_3} C₃} →
              {inst_3 : CategoryTheory.Category.{v_4, u_4} C₄} →
                {T : CategoryTheory.Functor C₁ C₂} →
                  {L : CategoryTheory.Functor C₁ C₃} →
                    {R : CategoryTheory.Functor C₂ C₄} →
                      {B : CategoryTheory.Functor C₃ C₄} → CategoryTheory.CatCommSq T L R B → ℕ