System/Library/PrivateFrameworks/CalendarNotification.framework

CALNMutableNotificationSound.h

NSObject
>
CALNNotificationSound

@class NSString;

@interface CALNMutableNotificationSound : CALNNotificationSound

@property (copy, nonatomic) NSString *alertTopic;

- (id)copyWithZone:(struct _NSZone { } *)a0;
- (void)setAlertTopic:(id)a0;

@end