proposition: Lemma cantor_perfect : perfect_set [set: cantor_space].
proof: Proof. by apply: perfect_diagonal => _; exists (true, false). Qed.
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)