proposition: Lemma symmetric_whiskers_swap_is_nat_trans {C : category} {M : monoidal C} (B : symmetric M) (x : C) : is_nat_trans _ _ (symmetric_whiskers_swap_nat_trans_data B x).
proof: Proof. intros y1 y2 g. exact (! monoidal_braiding_naturality_left B x y1 y2 g). Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Monoidal.WhiskeredBifunctors UniMath.CategoryTheory.Monoidal.Categories