@class FTQssAckResponse, FTPartialTextToSpeechStreamingResponse, FTBeginTextToSpeechStreamingResponse, FTFinalTextToSpeechStreamingResponse, NSObject;
@protocol FLTBFBufferAccessor, NSCopying;
@interface FTMutableTextToSpeechStreamingStreamingResponse : FTTextToSpeechStreamingStreamingResponse
@property (nonatomic) long long content_type;
@property (copy, nonatomic) FTQssAckResponse *contentAsFTQssAckResponse;
@property (copy, nonatomic) FTBeginTextToSpeechStreamingResponse *contentAsFTBeginTextToSpeechStreamingResponse;
@property (copy, nonatomic) FTPartialTextToSpeechStreamingResponse *contentAsFTPartialTextToSpeechStreamingResponse;
@property (copy, nonatomic) FTFinalTextToSpeechStreamingResponse *contentAsFTFinalTextToSpeechStreamingResponse;
@property (copy, nonatomic) NSObject<FLTBFBufferAccessor, NSCopying> *content;
+ (Class)content_mutableClassForType:(long long)a0;
+ (long long)content_typeForMutableObject:(id)a0;
+ (long long)content_typeForObject:(id)a0;
- (void)setContent:(id)a0;
- (id)init;
- (id)copyWithZone:(struct _NSZone { } *)a0;
@end