∀ {α : Type u_1} {E : Type u_2} {F : Type u_3} [inst : NormedAddCommGroup E] [inst_1 : NormedSpace ℝ E]
  [inst_2 : NormedAddCommGroup F] [inst_3 : NormedSpace ℝ F] {m : MeasurableSpace α} {μ : MeasureTheory.Measure α}
  (T : Set α → E →L[ℝ] F),
  MeasureTheory.FinMeasAdditive μ T →
    ∀ {f : MeasureTheory.SimpleFunc α E},
      MeasureTheory.Integrable (⇑f) μ →
        MeasureTheory.SimpleFunc.setToSimpleFunc T (-f) = -MeasureTheory.SimpleFunc.setToSimpleFunc T f