∀ {R : Type u_1} {L : Type u_3} {M : Type u_2} [inst : CommRing R] [inst_1 : LieRing L] [inst_2 : LieAlgebra R L]
  [inst_3 : LieRing M] [inst_4 : LieAlgebra R M] [inst_5 : IsLieAbelian M] [inst_6 : LieRingModule L M]
  [inst_7 : LieModule R L M] (c : ↥(LieModule.Cohomology.twoCocycle R L M)),
  LieAlgebra.IsExtension
    { toFun := fun x => (LieAlgebra.ofProd c) (0, x), map_add' := ⋯, map_smul' := ⋯, map_lie' := ⋯ }
    { toFun := fun x => ((LieAlgebra.ofProd c).symm x).1, map_add' := ⋯, map_smul' := ⋯, map_lie' := ⋯ }