∀ {A : Type u_1} {B : Type u_2} {C : Type u_3} {D : Type u_4} [inst : CategoryTheory.Category.{v_1, u_1} A]
  [inst_1 : CategoryTheory.Category.{v_2, u_2} B] [inst_2 : CategoryTheory.Category.{v_3, u_3} C]
  [inst_3 : CategoryTheory.Category.{v_4, u_4} D] (G : CategoryTheory.Functor B D) (F : CategoryTheory.Functor A B)
  (L : CategoryTheory.Functor A C) [inst_4 : G.PreservesRightKanExtension F L] [inst_5 : L.HasRightKanExtension F]
  (a : A),
  CategoryTheory.CategoryStruct.comp ((G.rightKanExtensionCompIsoOfPreserves F L).inv.app (L.obj a))
      (G.map ((L.rightKanExtensionCounit F).app a)) =
    (L.rightKanExtensionCounit (F.comp G)).app a