fact: Definition isfinite_to_DecidableEquality {X : UU} : isfinite X -> DecidableRelation X.
imports: UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions UniMath.MoreFoundations.NegativePropositions UniMath.Combinatorics.StandardFiniteSets UniMath.MoreFoundations.Subtypes