The code worked yesterday and I wanted to try different approaches today but it gives error today:

Oops, try again. Your function fails on is_prime(4). It returns True when it should return False.

What am I missing here?

```
def is_prime(x):
if x < 2:
return False
for n in range(2, x):
if n % x == 0:
return False
else:
return True
```