∀ {α : Type u_1} {𝕜 : Type u_14} {𝕜' : Type u_15} [inst : NormedField 𝕜] [inst_1 : NormedField 𝕜'] {l : Filter α}
  {ι : Type u_16} {s : Finset ι} {f : ι → α → 𝕜} {g : ι → α → 𝕜'},
  (∀ i ∈ s, f i =Θ[l] g i) → (fun x => ∏ i ∈ s, f i x) =Θ[l] fun x => ∏ i ∈ s, g i x