unsigned char result[16];
    const char* data = [self.setname UTF8String];
    CC_MD5(data, strlen(data), result);
    NSString *hash = [NSString stringWithFormat:@"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
                      result[0], result[1], result[2], result[3],
                      result[4], result[5], result[6], result[7],
                      result[8], result[9], result[10], result[11],
                      result[12], result[13], result[14], result[15]];

    NSString *ret = [NSString stringWithFormat:@"BIT-%@", hash];