fact: Definition isNeighborhood {X : UU} (B : X → (X → hProp) → hProp) := (∏ x, isfilter_imply (B x)) × (∏ x, isfilter_htrue (B x)) × (∏ x, isfilter_and (B x)) × (∏ x P, B x P → P x) × (∏ x P, B x P → ∃ Q, B x Q × ∏ y, Q y → B y P).
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.Topology.Filters UniMath.Algebra.Groups UniMath.Algebra.DivisionRig UniMath.Algebra.ConstructiveStructures