A sample of load & deleting a data in Swift Core Data

cleanup_auth_user_from_local_storage.swift

/**
     * Cleanup auth user info from local storage
     */
    func cleanup_auth_user_from_local_storage(){
        let authenticated_user_info = load_auth_user_info()
        if (authenticated_user_info != nil){
            let managed_object_context = app_delegate.managed_object_context
            managed_object_context.deleteObject(authenticated_user_info!)
            app_delegate.save_context(nil)
        }
    }

load_auth_user_info.swift

    /**
     * Load authenticated user's info if it is available
     */
    func load_auth_user_info() -> NSManagedObject?{
        let managed_object_context = app_delegate.managed_object_context
        let fetch_request = NSFetchRequest(entityName: "AuthenticatedUser")
        var authenticated_user :NSManagedObject?
        
        do{
            let results = try managed_object_context.executeFetchRequest(fetch_request)
            var authenticated_users = results as! [NSManagedObject]
            if (authenticated_users.count > 0){
                authenticated_user = authenticated_users[authenticated_users.count - 1]
            }
        }
        catch let error as NSError {
            print("Could not fetch record: \(error)")
        }
        
        return authenticated_user
    }