     ///
     /// Remove specific keys from being monitored in the background.
     ///
-    /// - Parameters: 
+    /// - Parameters:
     ///     - keys: Pass one or more keys that you would like to stop monitoring.
     public static func removeKeysFromBeingMonitored(keys: String...) {
         removeKeysFromBeingMonitored(keys: keys)


        if let index = registeredObservationKeys.index(of: key) {

            UserDefaults.standard.removeObserver(self, forKeyPath: key, context: nil)
            registeredObservationKeys.remove(at: index)

        }

        }
    }

    /// Overloaded version of Zephyr's synchronization method, **sync(keys:)**.
    ///
    /// If a custom UserDefaults object is passed in, Zephyr will synchronize that rather than UserDefaults.standard
    ///
    /// - Parameters:
    ///     - userDefaults: The UserDefaults object that should be synchronized with UbiquitousKeyValueStore.default
    ///       default value is UserDefaults.standard
    ///     - keys: If you pass a one or more keys, only those key will be synchronized. If no keys are passed, than all NSUserDefaults will be synchronized with NSUbiquitousKeyValueStore.
    public static func sync(keys: String..., userDefaults: UserDefaults = UserDefaults.standard) {
        shared.userDefaults = userDefaults
        sync(keys: keys)
    }

    /// Overloaded version of Zephyr's synchronization method, **sync(keys:)**.
    ///
    /// If a custom UserDefaults object is passed in, Zephyr will synchronize that rather than UserDefaults.standard
    ///
    /// - Parameters:
    ///     - userDefaults: The UserDefaults object that should be synchronized with UbiquitousKeyValueStore.default
    ///       default value is UserDefaults.standard
    ///     - keys: An array of keys that should be synchronized between NSUserDefaults and NSUbiquitousKeyValueStore.
    public static func sync(keys: [String], userDefaults: UserDefaults = UserDefaults.standard) {
        shared.userDefaults = userDefaults
        sync(keys: keys)
    }

    /// Add specific keys to be monitored in the background. Monitored keys will automatically
    /// be synchronized between both data stores whenever a change is detected
    ///
