rintro rfl
case mpr.mpr
G : Type u_1
inst✝ : Group G
h : ∀ (g h : G), ⁅g, h⁆ = 1
g : G
⊢ g = 1 → g ∈ ⨆ i, ⨆ i_1, Subgroup.closure {⁅i, i_1⁆}
case mpr.mpr
G : Type u_1
inst✝ : Group G
h : ∀ (g h : G), ⁅g, h⁆ = 1
⊢ 1 ∈ ⨆ i, ⨆ i_1, Subgroup.closure {⁅i, i_1⁆}