use Deserialize;
/// The `event` field of a BitTorrent announce request ([BEP 3]).
///
/// Clients send `started` on their first announce for a torrent, `completed`
/// when the download finishes, and `stopped` when they shut down. All other
/// announces omit the field (represented here as `None`).
///
/// [BEP 3]: https://www.bittorrent.org/beps/bep_0003.html