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916823d | 1 2 3 4 5 6 7 8 9 10 11 12 | import Mathlib
open CategoryTheory
def RingCat.units : RingCat.{u} ⥤ Grp.{u} where
obj R := .of Rˣ
map f := Grp.ofHom (Units.map f.hom)
theorem exists_leftAdjoint_unitFunctor :
∃ (left : Grp.{u} ⥤ RingCat.{u}), Nonempty (left ⊣ RingCat.units.{u}) := by
sorry
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