```
def is_prime(x):
if x < 2:
return False
elif x == 2 or x == 3:
return True
for n in range(2, x-1):
if x % n == 0:
return False
else:
return True.
```

I thought I had this one down easy; but it will not work with nine (it returns true). My best guess if that that the x % n == 0 under my last if statement is running 9/2 != 0 therefore it's true... Do i need something above "return False" to iterate to other numbers in the final if statement? Thanks!