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YandexMusic.API/Requests/Playlist/YGetPlaylistsBuilder.cs

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+using System.Net;
+
+using YandexMusic.API.Common;
+using YandexMusic.API.Models.Common;
+using YandexMusic.API.Models.Playlist;
+using YandexMusic.API.Requests.Common;
+using YandexMusic.API.Requests.Common.Attributes;
+
+namespace YandexMusic.API.Requests.Playlist
+{
+    [YApiRequest(WebRequestMethods.Http.Post, "playlists/list")]
+    public class YGetPlaylistsBuilder : YRequestBuilder<YResponse<List<YPlaylist>>, IEnumerable<(string User, string Kind)>>
+    {
+        public YGetPlaylistsBuilder(YandexMusicApi yandex, AuthStorage auth) : base(yandex, auth)
+        {
+        }
+
+        protected override HttpContent GetContent(IEnumerable<(string User, string Kind)> playlistIds)
+        {
+            return new FormUrlEncodedContent(new Dictionary<string, string> {
+                { "playlist-Ids", string.Join(",", playlistIds.Select(t => $"{t.User}:{t.Kind}")) }
+            });
+        }
+    }
+}