Definition fginv_binopfun (X : hSet) : binopfun (free_monoid (setcoprod X X)) (setwithbinop_rev (free_monoid (setcoprod X X))). Proof. refine (binopfuncomp (free_monoidfun _) (reverse_binopfun _)). exact (coprodcomm X X). Defined.
Require Import UniMath.MoreFoundations.Subtypes. Require Import UniMath.MoreFoundations.Sets. Require Import UniMath.Algebra.Monoids. Require Import UniMath.Algebra.Groups. Require Import UniMath.Algebra.IteratedBinaryOperations. Require Import UniMath.Combinatorics.Lists.