fact: Definition open_po : po (@Open X) := make_po _ (isporesrel _ _ (subtype_containment_ispreorder X)).
imports: UniMath.Algebra.RigsAndRings UniMath.MoreFoundations.Subtypes UniMath.Topology.Topology UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.Categories.PreorderCategories UniMath.CategoryTheory.Categories.Commring UniMath.AlgebraicGeometry.Topology