Ltac start_unchanged :=
    red; intros; eapply one_leaderLog_per_term_unchanged; eauto; subst.(* solve invariant by lemma which shows leader logs do not change *)
  Ltac unchanged lem :=
    start_unchanged; apply lem.

Lemma one_leaderLog_per_term_append_entries : refined_raft_net_invariant_append_entries one_leaderLog_per_term.