public Library CheckOutBook(Book book, Student student, DateTime checkedOutDate)
{
var result = new Library();
result.ExpectedReturnDate = checkedOutDate.AddMonths(1);
result.CheckOutDate = checkedOutDate;
return result;
}
public Library CheckInBook(Book book, DateTime droppedOffDate)
{
var result = new Library();
result.ExpectedReturnDate = null;
result.ActualReturnDate = droppedOffDate;
return result;
}