code: public GetPlaylistsTracksRequest.Builder getPlaylistsTracks(String playlist_id) {
      return new GetPlaylistsTracksRequest.Builder(accessToken)
              .setDefaults(httpManager, scheme, host, port)
              .playlist_id(playlist_id);
    }
docs: Get a playlists tracks.
  
  @param playlist_id The playlists ID.
  @return A {@link GetPlaylistsTracksRequest.Builder}.
  @see <a href="https://developer.spotify.com/web-api/user-guide/#spotify-uris-and-ids">Spotify: URLs &amp; IDs</a>