fact: Definition pr1ZFS (X : ZFS) : preZFS := pr1 X.
imports: UniMath.Foundations.PartB UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.Foundations.HLevels UniMath.Combinatorics.WellOrderedSets UniMath.Combinatorics.OrderedSets UniMath.MoreFoundations.DecidablePropositions UniMath.MoreFoundations.Propositions