System/Library/PrivateFrameworks/ContactsFoundation.framework

_CNBlockTask.h

NSObject
>
CNTask

@interface _CNBlockTask : CNTask {
    id /* block */ _block;
}

- (id)initWithBlock:(id /* block */)a0;
- (id)run:(id *)a0;
- (id)initWithName:(id)a0 block:(id /* block */)a1;
- (id)initWithName:(id)a0;
- (void).cxx_destruct;

@end