Error code: Oops, try again. median([4, 5, 5, 4]) returned 4 instead of 4.5

I do not understand why this isn't returning 4.5?

```
Replace this line with your code.
def median(lst):
sorted(lst)
if len(lst)%2 != 0 and len(lst) > 1:
return lst[(len(lst)-1)/2]
elif len(lst) == 1:
return lst[0]
else:
return (lst[len(lst)/2-1] + lst[(len(lst)+2)/2]-1)/2
print median([4,5,3,2])
```