{C : Type u₁} →
  [inst : CategoryTheory.Category.{v₁, u₁} C] →
    {D : Type u₂} →
      [inst_1 : CategoryTheory.Category.{v₂, u₂} D] →
        {F G H : CategoryTheory.Functor C D} →
          CategoryTheory.NatTrans F G → CategoryTheory.NatTrans G H → CategoryTheory.NatTrans F H