private static Task <TResult> GetFeedAsync <TResult, TQuery>(SpreadsheetsService service, TQuery query, IAggregateProgress progress, CancellationToken cancellationToken)
where TQuery : FeedQuery
where TResult : AtomFeed
{
var userData = new object();
service.QueryFeedAync(query.Uri, query.ModifiedSince, userData);
return(QueryFeedAsync <TResult>(service, userData, progress, cancellationToken));
}