fact: Definition tightap_aprel {X : UU} (ap : tightap X) : aprel X := pr1 ap ,, (pr1 (pr2 ap)).
imports: UniMath.Algebra.BinaryOperations UniMath.Foundations.Propositions UniMath.MoreFoundations.Sets UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions