(* Inducitve step - prove that the invariant indeed holds *)
Hypothesis HIstep : S_inv.

(* Specifications: *)
Lemma s_step_cohI : s_step_coh_t CohI (t_snd st) send_stepI.
Definition snd_transI := SendTrans s_safe_cohI s_safe_inI s_safe_defI s_step_cohI.