{S : Type} : S -> FreeAbGroup S := abel_unit o freegroup_in.
Require Import Basics.Overture Basics.Tactics Basics.Equivalences. Require Import Types.Sigma Types.Forall Types.Paths. Require Import WildCat.Core WildCat.EquivGpd WildCat.Universe. Require Import Algebra.AbGroups.AbelianGroup Algebra.AbGroups.Abelianization. Require Import Algebra.Groups.FreeGroup. Require Import Spaces.List.Core.