∀ {α : Type u_1} {m0 : MeasurableSpace α} {μ : MeasureTheory.Measure α} {s : Set α},
  MeasurableSet s →
    ∀ {t : Set α} {m : ℕ → MeasureTheory.Measure α},
      (∀ (n : ℕ), (m n) t ≠ ⊤) → μ = MeasureTheory.Measure.sum m → μ (MeasureTheory.toMeasurable μ t ∩ s) = μ (t ∩ s)