proposition: Lemma InPtE k v f : C k -> f = pts k v -> (k, v) \In f.
proof: Proof. by move=>W ->; apply: In_condPt W. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)