     
     private func sync(
         userId:String?,
-        fireBase:FDatabase,
+        firebase:FDatabase,
         users:FDatabaseUsers,
         completion:@escaping((FDatabaseUsersItem) -> ()))
     {

            return
        }
        
        let userId:String = fireBase.create(
            parent:users,
            data:userJson)
        user.identifier = userId

    
    func loadFromFirebase(
        userId:String,
        firebase:FDatabase,
        users:FDatabaseUsers,
        completion:@escaping((FDatabaseUsersItem) -> ()))
    {
        firebase.load(
            parent:users,
            identifier:userId)
        { [weak self] (user:FDatabaseUsersItem?) in
