proposition: Lemma pr_pred0 mu : \P_[mu] pred0 = 0.
proof: Proof. by rewrite /pr psum_eq0 // => x /=; rewrite mul0r. Qed.
imports: mathcomp(all_ssreflect all_algebra) mathcomp.classical(boolp classical_sets mathcomp_extra) xfinmap ereal reals discrete topology realseq realsum