proposition: Lemma is_invertible_2cell_rinvunitor {a b : C} (f : C ⟦ a, b ⟧) : is_invertible_2cell (rinvunitor f).
proof: Proof. exists (runitor f). abstract (apply (rinvunitor_runitor _ ,, runitor_rinvunitor _)). Defined.
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