Access Cosmos DB created document properties using shadow properties with EF Core

BooksContext.cs

public void ShowCosmosDBState()
{
    foreach (var book in Books)
    {
        Console.WriteLine($"{book.Title}, etag: {Entry<Book>(book).Property("_etag").CurrentValue}, " +
            $"self: {Entry(book).Property("_self").CurrentValue}, " +
            $"ts: {Entry(book).Property("_ts").CurrentValue}");
        Console.WriteLine();
    }
}