proposition: Lemma filter_incl: forall A f (l: list A), incl (filter f l) l.
proof: Proof. intros. hnf. intros. rewrite filter_In in H. destruct H; auto. Qed.
imports: Coq.Lists.List Coq.micromega.Lia Coq.Sorting.Permutation Coq.ZArith.ZArith_base Coq.ZArith.Zcomplements Coq.Logic.FunctionalExtensionality CertiGraph.lib.Coqlib CertiGraph.lib.EquivDec_ext VST.zlist.sublist VST.zlist.list_solver