# The programmer's wife sends out
# her husband to buy:
# "Buy two eggs,
eggs = 0
# and when they have sausages,
sausages = 0
# buy ten.
# The programmer goes into the shop:
shop = ('Bread','Butter','Meat','Sausages','Water','Eggs')
# "Hello, do you have sausages?"
if 'Sausages' in shop:
#...