∀ (R : Type u_3) (M : Type u_4) [inst : TopologicalSpace R] [inst_1 : TopologicalSpace M] [inst_2 : CommSemiring R]
  [inst_3 : AddCommMonoid M] [inst_4 : Module R M] (x : TrivSqZeroExt R M), (TrivSqZeroExt.fstCLM R M) x = x.fst