python定义函数遇到的问题

Question

#定义了一个列表

moshushis = ['张三','李四','王二']

#定义一个对函数对列表里的元素进行修改

def make_great(greats):
    num = 0
    for great in greats:
        greats[num] = great + 'the Great'
        num = num + 1
make_great(moshushis)
print(moshushis)

#我尝试用while去实现，最后调用函数的时候返回的却是一个空列表？ 
def make_great_while(great_whiles):
    great1_whiles = []
    while great_whiles:
        great1 = great_whiles.pop() + ' hello'
        great1_whiles.append(great1)
    great_whiles = great1_whiles[:]
make_great_while(moshushis)
print(moshushis)
 

Answer 1

def make_great_while(great_whiles):
    great1_whiles = []
    while great_whiles:
        great1 = great_whiles.pop() + ' hello'
        great1_whiles.append(great1)
    return great1_whiles[:]
moshushis = make_great_while(moshushis)
print(moshushis)