∀ {R : Type u_2} {S : Type u_1} [inst : CommSemiring R] [inst_1 : Semiring S] [inst_2 : Algebra R S]
  (M : Submodule R S), M.rTensorOne' ∘ₗ ↑(TensorProduct.comm R ↥⊥ ↥M) ∘ₗ (TensorProduct.mk R ↥⊥ ↥M) 1 = LinearMap.id