enum {
    // YouTube Heartbeat error codes
    YT_HEARTBEAT_CANNOT_AUTHENTICATE                    = 513,
    YT_HEARTBEAT_NO_ACTIVE_PURCHASE_AGREEMENT           = 514,
    YT_HEARTBEAT_CONCURRENT_PLAYBACK                    = 515,
    YT_HEARTBEAT_UNUSUAL_ACTIVITY                       = 516,
    YT_HEARTBEAT_STREAMING_UNAVAILABLE                  = 517,
    YT_HEARTBEAT_CANNOT_ACTIVATE_RENTAL                 = 518,
};