[Tutor] primality testing

[Peter Jakubowicz]

I've written a small program to test whether a number is prime. But in the 
back of my mind, I feel it should be simpler and shorter. Can anyone 
advise. Thanks.

from math import sqrt

def prime(n):
     factor = 0
     for i in range(2, sqrt(n) + 1):
         if n % i == 0:
             factor = factor + 1
             break
     if factor == 0:
         print "Prime"
     else:
         print "Composite"