∀ {Γ : Type u_2} {R : Type u_1} [inst : AddCommMonoid Γ] [inst_1 : LinearOrder Γ] [inst_2 : IsOrderedCancelAddMonoid Γ]
  [inst_3 : CommRing R] {x : HahnSeries Γ R} (h : 0 < (x - 1).orderTop), ↑⋯.unit⁻¹ * x = 1