python homework——The second week

3-1
names=['Mike','John','Jack']
for name in names:
    print(name)

3-4
guests=['Stark','Mike','Einstein']
for guest in guests:
    print("Could you come to have a dinner with me,"+guest+"?")

3-5
print('Mike can't come')
guests[1]='Kate'
for guest in guests:
    print("Could you come to have dinner with me,"+guest+"?")
3-6
print('I have found a bigger table.')
guests.insert(0,'Mask')
guests.insert(2,'Obama')
guests.append('lening')
for guest in guests:
    print('Could you come to have dinner with me,'+guest+'?')
3-7
print('Sorry, I can only invite 2 guests')
for value in range(0,4):
    guest=guests.pop()

    print('Sorry, '+guest)

for guest in guests:
    print('You are still in the list')

del guests[0]
del guests[0]
print(guests)
3-8
places=['The Great Wall','The peking University','London']
print(places)
print(sorted(places))
print(places)
print(sorted(places,reverse=True))
print(places)
places.reverse()
print(places)
places.reverse()
print(places)
places.sort()
print(places)
places.sort(reverse=True)
print(places)
3-9
print('There are '+str(len(guests))+'guests to come to my dinner.')
4-1
pizzas=['a','b','c']
for pizza in pizzas:
    print(pizza)

for pizza in pizzas:
    print('I like '+pizza+' pizza')

print('I really love pizza')
4-2
animals=['dog','cat,'bird']
for animal in animals:
    print('A '+animal+' would make a great pet')

print('Any of these animals would make a great pet')
4-3
for num in range(1,21):
    print(num)