public static Task<LobbyOperationResponse> DenyLobbyParticipantsAsync(this LobbyManager mgr,
     IEnumerable<ConversationParticipant> lobbyParticipants, LobbyDenyOptions options)
 {
   return Task<LobbyOperationResponse>.Factory.FromAsync(mgr.BeginDenyLobbyParticipants,
       mgr.EndDenyLobbyParticipants, lobbyParticipants, options,
       null);
 }
 public static Task<LobbyOperationResponse> DenyLobbyParticipantsAsync(this LobbyManager mgr,
     IEnumerable<ConversationParticipant> lobbyParticipants, LobbyDenyOptions options)
 {
     return Task<LobbyOperationResponse>.Factory.FromAsync(mgr.BeginDenyLobbyParticipants,
         mgr.EndDenyLobbyParticipants, lobbyParticipants, options,
         null);
 }