proposition: Lemma lunitor_lwhisker {a b c : C} (f : C⟦a, b⟧) (g : C⟦b, c⟧) : rassociator _ _ _ • (f ◃ lunitor g) = runitor f ▹ g.
proof: Proof. use lhs_left_invert_cell. { apply is_invertible_2cell_rassociator. } cbn. apply pathsinv0. apply runitor_rwhisker. Qed.
imports: UniMath.Tactics.EnsureStructuredProofs UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.PrecategoryBinProduct