proposition: Lemma map_proj1_sig_sig_In {A} (ls : list A) : List.map (@proj1_sig _ _) (sig_In ls) = ls.
proof: Proof. induction ls; simpl; f_equal; rewrite map_map; simpl; assumption. Qed.
imports: Fiat.Common.Coq__8_4__8_5__Compat Coq.ZArith.ZArith Coq.Lists.List Coq.Lists.SetoidList Coq.Bool.Bool Fiat.Common Fiat.Common.List.Operations Fiat.Common.Equality Fiat.Common.List.FlattenList Fiat.Common.LogicFacts