∀ {α : Type u_1} [B : Bornology α] (m : PseudoMetricSpace α),
  (∀ (s : Set α), Bornology.IsBounded s ↔ Bornology.IsBounded s) →
    (Bornology.cobounded α).sets = {s | ∃ C, ∀ x ∈ sᶜ, ∀ y ∈ sᶜ, dist x y ≤ C}