∀ {α : Type u_1} {β : Type u_2} [inst : UniformSpace α] [inst_1 : Group α] [IsUniformGroup α] {ι : Type u_3}
  {l : Filter ι} {f f' : ι → β → α} {g g' : β → α},
  TendstoUniformly f g l → TendstoUniformly f' g' l → TendstoUniformly (f * f') (g * g') l