∀ {R : Type u_2} {S : Type u_3} [inst : Ring R] [inst_1 : Ring S] {f : R →+* S} (X : ModuleCat S),
  Function.LeftInverse (AddEquiv.refl ↑((ModuleCat.restrictScalars f).obj X)).invFun
    (AddEquiv.refl ↑((ModuleCat.restrictScalars f).obj X)).toFun