IF條件判斷：
#示例：
age = 3
if age >= 18:
print 'adult'
elif age >= 6:
print 'teenager'
else:
print 'kid'
for...in循環(huán)
#示例1
names = ['Michael', 'Bob', 'Tracy']
for name in names:
print name
#示例2
sum = 0
for x in range(101):
sum = sum + x
print sum
while循環(huán)
sum = 0
index = 1
while index <= 100:
sum = sum + index
print sum
