proposition: Lemma semi_additive2E : semi_additive2 mu = additive2 mu.
proof: Proof. rewrite propeqE; split=> [amu A B ? ? ?|amu A B ? ? _ ?]; last by rewrite amu. by rewrite amu //; exact: measurableU. 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)