proposition: Lemma CountableT_cardinality {X : Type} : CountableT X <-> le_cardinal X nat.
proof: Proof. reflexivity. Qed.
imports: Coq(ClassicalChoice) Coq(ProofIrrelevance) Coq(FunctionalExtensionality) Coq(Description) ZornsLemma(FunctionPropertiesEns) ZornsLemma(Relation_Definitions_Implicit) ZornsLemma(CSB) ZornsLemma(EnsemblesSpec) ZornsLemma(ZornsLemma) ZornsLemma(EnsemblesImplicit) ZornsLemma(CountableTypes) ZornsLemma(FiniteTypes) ZornsLemma(InfiniteTypes) Coq(RelationClasses)