proposition: Lemma measurableC A : measurable A -> measurable (~` A).
proof: Proof. by move=> mA; rewrite -setTD; exact: measurableD. Qed.
imports: mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) reals ereal signed topology normedtype sequences esum numfun HB(structures)