fact: Definition dualelement' {n : nat} (i : ⟦ n ⟧%stn) : ⟦ n ⟧%stn.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.Combinatorics.Maybe UniMath.Combinatorics.StandardFiniteSets UniMath.Algebra.Domains_and_Fields UniMath.Algebra.RigsAndRings