proposition: Proposition rassociator_lassociator_h' {C : double_cat} {w x y z : C} (f : w -->h x) (g : x -->h y) (h : y -->h z) : transportf_square (id_v_left _) (id_v_left _) (rassociator_h f g h ⋆v lassociator_h f g h) = id_v_square _.
proof: Proof. rewrite rassociator_lassociator_h. rewrite transportfb_square. apply idpath. Qed.
imports: UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Prelude UniMath.CategoryTheory.TwoSidedDisplayedCats.TwoSidedDispCat UniMath.CategoryTheory.TwoSidedDisplayedCats.Univalence UniMath.Bicategories.Core.Bicat UniMath.Bicategories.DoubleCategories.Core.DoubleCats UniMath.Bicategories.DoubleCategories.DerivedLaws.TransportLaws UniMath.Bicategories.DoubleCategories.Core.DoubleCats UniMath.Bicategories.DoubleCategories.Core.UnivalentDoubleCats