fact: Hypothesis refine_separates: forall x y : X, x != y -> exists n, forall (U : set X) e, @refine_apx n U e x -> ~@refine_apx n U e y.
imports: mathcomp(all_ssreflect ssralg ssrint ssrnum interval rat) mathcomp(finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality) reals signed topology HB(structures)