This is my code, I don't understand the problem.

def is_prime(x):

x = abs(x)

if(x == 0 or x == 1):

return False

n = x - 1

while(n > 1):

if(x % n == 0):

return False

n -= 1

return True

print is_prime(int(raw_input("Give a number: ")))

The message I get is "Oops, try again. Your function fails on is_prime(-7). It returns True when it should return False."