proposition: Theorem inr_red {A B : Type} {C : Book_1_5_sum A B -> Type} f g { b : B } : Book_1_5_ind A B C f g (inr b) = g b.
proof: Proof. reflexivity. Defined.
imports: HoTT(Basics Types HProp HSet Projective TruncType Truncations Modalities.Notnot Modalities.Open Modalities.Closed BoundedSearch Equiv.BiInv Spaces.Nat Spaces.Torus.TorusEquivCircles Metatheory.Core Metatheory.FunextVarieties)