∀ {α : Type u_1} {β : Type u_2} {γ : Type u_3} [inst : MeasurableSpace α] {μ : MeasureTheory.Measure α}
  [inst_1 : TopologicalSpace γ] [inst_2 : MeasurableSpace β] {ν : MeasureTheory.Measure β} {f : α → β} {g : β → γ}
  (hg : MeasureTheory.AEStronglyMeasurable g ν) (hf : MeasureTheory.MeasurePreserving f μ ν),
  (MeasureTheory.AEEqFun.mk g hg).compMeasurePreserving f hf = MeasureTheory.AEEqFun.mk (g ∘ f) ⋯