I have a lot of core database classes that shares the same two functions (please see below).

It seem there should be a better way to do this? Is it possible to create a generic function / Protocol for this?

final class ChecklistHelper {      static let shared = ChecklistHelper()      private func fetchFirstInDatabaseWith(predicate: NSPredicate) -> Checklist? {         guard let cd = ChecklistCD.mr_findFirst(with: predicate) else { return nil }         return Checklist(manageObject: cd)     }      private func fetchAllInDatabaseWith(predicate: NSPredicate) -> [Checklist]? {         guard let cds = ChecklistCD.mr_findAll(with: predicate) as? [ChecklistCD] else { return nil }         return cds.map { Checklist(manageObject: $  0) }     } }  ...   final class RecipieHelper {      static let shared = RecipieHelper()      private func fetchFirstInDatabaseWith(predicate: NSPredicate) -> Recipie? {         guard let cd = RecipieCD.mr_findFirst(with: predicate) else { return nil }         return Recipie(manageObject: cd)     }      private func fetchAllInDatabaseWith(predicate: NSPredicate) -> [Recipie]? {         guard let cds = RecipieCD.mr_findAll(with: predicate) as? [RecipieCD] else { return nil }         return cds.map { Recipie(manageObject: $  0) }     } }