∀ {R : Type u} [inst : CommSemiring R] {M : Type u_1} [inst_1 : AddCommMonoid M] [inst_2 : Module R M] {S : Type v}
  [inst_3 : CommSemiring S] [inst_4 : Algebra R S] (t : TensorProduct R S M),
  ∃ n ψ p, (LinearMap.rTensor M ψ.toLinearMap) p = t