fact: Structure ahom := AHom {ahval :> 'Hom(aT, rT); _ : ahom_in {:aT} ahval}.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype div tuple finfun bigop ssralg) mathcomp(finalg zmodp matrix vector poly)