∀ {α : Type u_1} {γ : Type u_3} [inst : MeasurableSpace α] {μ : MeasureTheory.Measure α} [inst_1 : TopologicalSpace γ]
  [inst_2 : Mul γ] [inst_3 : ContinuousMul γ] (f g : α →ₘ[μ] γ), (f * g).toGerm = f.toGerm * g.toGerm