∀ {α : Type u_1} {β : Type u_2} {mα : MeasurableSpace α} {mβ : MeasurableSpace β} {γ : Type u_4}
  {mγ : MeasurableSpace γ} {f : β → γ} (κ : ProbabilityTheory.Kernel α β),
  Measurable f → ∀ (a : α), (κ.map f) a = MeasureTheory.Measure.map f (κ a)