∀ {α : Type u_1} {m : MeasurableSpace α} {μ : MeasureTheory.Measure α} {E : Type u_8} [inst : NormedAddCommGroup E]
  [inst_1 : NormedSpace ℝ E] {f : α → NNReal},
  Measurable f →
    ∀ (u : ↥(MeasureTheory.Lp E 1 (μ.withDensity fun x => ↑(f x)))), MeasureTheory.MemLp (fun x => f x • ↑↑u x) 1 μ