∀ {𝕜 : Type u} [inst : NontriviallyNormedField 𝕜] {x : 𝕜} {s : Set 𝕜} [inst_1 : LinearOrder 𝕜] [IsStrictOrderedRing 𝕜]
  [OrderTopology 𝕜] {g : 𝕜 → 𝕜} {g' : 𝕜},
  AccPt x (Filter.principal s) → HasDerivWithinAt g g' s x → AntitoneOn g s → g' ≤ 0