I've already solved this exercise inefficiently using the Sieve of Erastothenes, but I'm trying again with the instructions provided. I think I'm 90% of the way there.

Whenever I run the code, I get:

"Oops, try again. Your function fails on is_prime(0). It returns None when it should return False. "

I think the code runs into trouble as it tries to divide by zero and results in 'None', can anyone help me out?

Thanks

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