customers = [

dict(id=1, total=200, coupon_code='F20'), # F20: fixed, £20

dict(id=2, total=150, coupon_code='P30'), # P30: percent, 30%

dict(id=3, total=100, coupon_code='P50'), # P50: percent, 50%

dict(id=4, total=110, coupon_code='F15'), # F15: fixed, £15

]

for customer in customers:

code = customer['coupon_code']

if code == 'F20':

customer['discount'] = 20.0

elif code == 'F15':

customer['discount'] = 15.0

elif code == 'P30':

customer['discount'] = customer['total'] * 0.3

elif code == 'P50':

customer['discount'] = customer['total'] * 0.5

else:

customer['discount'] = 0.0

for customer in customers:

print(customer['id'], customer['total'], customer['discount'])