proposition: Lemma isotoid_2_1_rwhisker {B : bicat} (HB : is_univalent_2_1 B) {a b c : B} {f₁ f₂ : a --> b} (α : invertible_2cell f₁ f₂) (g : b --> c) : maponpaths (λ z : a --> b, z · g) (isotoid_2_1 HB α) = isotoid_2_1 HB (α ▹ g ,, is_invertible_2cell_rwhisker _ (pr2 α)).
proof: Proof. use (invmaponpathsincl (idtoiso_2_1 _ _)). - apply isinclweq. exact (HB _ _ _ _). - use subtypePath. { intro ; apply isaprop_is_invertible_2cell. } etrans. { refine (!_). apply idtoiso_2_1_rwhisker. } rewrite !idtoiso_2_1_isotoid_2_1. apply idpath. Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.Bicategories.Core.Bicat UniMath.Bicategories.Core.Unitors UniMath.Bicategories.Core.Invertible_2cells UniMath.Bicategories.Morphisms.Adjunctions UniMath.Bicategories.Core.Univalence