public ExpectedCourseBooking(IEnumerable <Guid> sessionIds, Guid customerId)
 {
     SessionIds = new List <Guid>(sessionIds);
     Customer   = new ApiCustomerKey {
         id = customerId
     };
     SessionBookingIds = new List <Guid>();
 }
 public ExpectedBooking(Guid sessionId, Guid customerId)
 {
     Session = new ApiSessionKey {
         id = sessionId
     };
     Customer = new ApiCustomerKey {
         id = customerId
     };
     HasAttended   = null;
     PaymentStatus = Constants.PAYMENT_STATUS_PENDING_INVOICE;
 }