∀ {α : Type u_1} {β : Type u_2} [inst : ConditionallyCompleteLinearOrder β] {f : Filter α} {u : α → β} {x : β},
  autoParam (Filter.IsCoboundedUnder (fun x1 x2 => x1 ≤ x2) f u) Filter.le_limsup_iff._auto_1 →
    autoParam (Filter.IsBoundedUnder (fun x1 x2 => x1 ≤ x2) f u) Filter.le_limsup_iff._auto_3 →
      (x ≤ Filter.limsup u f ↔ ∀ y < x, ∃ᶠ (a : α) in f, y < u a)