proposition: Lemma umPt0E (k : K) (v : V) : (k \\-> v == Unit) = false.
proof: Proof. by apply: (introF idP)=>/eqP/unitbP; rewrite um_unitbPt. Qed.
imports: Coq(ssreflect ssrbool ssrfun) mathcomp(ssrnat eqtype seq path bigop) pcm(options prelude finmap seqperm pred seqext) pcm(pcm morphism)