PyCode of a Veggie Shop

import sys

def veggie_quatity(msg):
    while True:
        try:
            quantity = int(raw_input(msg))
            if quantity < 0:
                print "Error, Enter Positive Number!"
                continue
            return quantity
        except Exception, e:
            print e

def bye():
    shop_ticket()
    sys.exit(0)

def shop_ticket():
    template = '%-10s%10d%10.2f\n'
    print "Item\t\tQuantity\tCost\n"
    for item in veggie_menu:
       if item != 'Q':
           if veggie_menu[item][1] > 0:
           print template%(veggie_menu[item][3],
                      veggie_menu[item][1], veggie_menu[item][2])

#  use dictionary store your key as veggie types and values for
#  these constants as follow
#  [price_of_veggie_type, counter, total_veggie_order, veggie_names]
veggie_menu = {
       "L": [0.89, 0, 0.0, 'Lettuce'], "G" :[2.50, 0, 0.0, 'Green Beans'],
       "P" :[0.50, 0, 0.0, 'Peppers'], "T" :[0.75, 0, 0.0, 'Tomatoes'],
       "O" :[0.50, 0, 0.0, 'Onions'], "Q" : bye,
     }

while True:
    print """
         Veggie Menu:
         Select Item by letter Choice
         L = Lettuce
         G = Green Beans
         P = Peppers
         T = Tomatoes
         O = Onions
         Q = Quit Program
         """
    try:
        veggieType = (raw_input("What Veggie would you like to order? Enter Q to Quit: ")).upper();
        if veggieType == 'Q':
        veggie_menu[veggieType]()
        if veggieType not in veggie_menu.keys():
        print "Error", veggieType, "doesn't exists"
        continue

        how_many = veggie_quatity("How many "+ veggie_menu[veggieType][3]+
                                  " would you like to order? ")

        veggie_menu[veggieType][1] += how_many
        veggie_menu[veggieType][2] += (how_many * veggie_menu[veggieType][0])

    except Exception, e:
        print e