33@interface NSDictionary (OOExtensions)
36- (NSDictionary *) dictionaryByAddingObject:(
id)object forKey:(
id)key;
37- (NSDictionary *) dictionaryByRemovingObjectForKey:(
id)key;
38- (NSDictionary *) dictionaryByAddingEntriesFromDictionary:(NSDictionary *)dictionary;