Invert the list by exchanging the first and last element, the second and second last, and so on

So Basically the task is to invert the List by changing the first element with the last one, the second one with the second last etc… This is what i tried, but nothing happend in the end. Do you have any ideas whats not working here or what different approach i should try?

list=[3,6,9,12,15,18,21,24,27,30]
y = 0
x = len(list)-1
while y <= x:
    for i in list:
        list[y],list[x]=list[x],list[y]
        y+=1
        x-=1
for i in list:
    print(i)

Answer

All the other solutions are good approaches, but if you were specifically asked to write the logic for inverting the list by changing the first element with last element and so on..here,

y = 0
x = len(list)-1
while y < x:
    list[y],list[x]=list[x],list[y]
    y+=1
    x-=1
for i in list:
    print(i)