# Fetch my orders
orders = repo.get_orders_for(self._customer[0])

if len(orders) > 0:
    current_order_no = -1
    for (order_number, quantity, pid) in orders:

        # Print new heading if needed
        if order_number is not current_order_no:
            print("Order #{}".format(order_number))
            current_order_no = order_number

        print("    Product #{}, ordered x{}".format(pid, quantity))

SELECT OrderNumber, Quantity, Product_ProductId FROM `order` JOIN `orderitem` ON `order`.OrderNumber = Order_OrderNumber WHERE CustomerAccount_CustomerId=%s ORDER BY OrderNumber

>>> a=1234
>>> b=1234
>>> a is b
False
>>> a=12
>>> b=12
>>> a is b
True

from itertools import groupby
from operator import itemgetter

# Fetch my orders
orders = repo.get_orders_for(self._customer[0])

for order_number, items in groupby(orders, key=itemgetter(0)):
    print("Order #{}".format(order_number))
    for _, quantity, pid in items:
        print("    Product #{}, ordered x{}".format(pid, quantity))