Regex Prime

regexPrime.py

#!/usr/bin/python 
import re

def regex_prime(n):
    l = "1" * n
    return re.match(r"^1?$|^(11+?)\1+$", l) == None

while True:
    n = raw_input("\nEnter a number and test for prime:")
    try:
        print(regex_prime(int(n)))
    except ValueError:
        print("not an integer\n")