fact: Definition free_abgr (X : hSet) : abgr := abgr_of_gr (free_abgr' X) (iscomm_free_abgr X).
imports: UniMath.MoreFoundations.Subtypes UniMath.MoreFoundations.Sets UniMath.Algebra.Monoids UniMath.Algebra.Groups UniMath.Algebra.IteratedBinaryOperations UniMath.Combinatorics.Lists