Accept input and determine prime numbers

is_prime.py

import string

def is_prime(n):
    n = abs(int(n))
    if n < 2:
        return False
    if n == 2:
        return True
    if not n & 1:
        return False
    for x in range(3, int(n**0.5)+1, 2):
        if n % x == 0:
            return False
    return True

def check_true_false(q):
    if q == False:
        if y == "A":
            print "%d is not a prime number." % z
        else:
            pass
    else:
        print "%d is a prime number." % z

x = int(input("Select range: 0 - "))
y = string.upper(raw_input("Show [a]ll or only [P]rimes? a/P: "))
z = 0
while z < len((range(x+1))):
    check_true_false(is_prime(z))
    z = z + 1

The ultimate goal is to create a number of tools to determine numerical theories from a set of numbers. I want to be able to pass those sets of numbers around and determine how they relate. For example, find a set of golden ratios and then determine if there is a pattern of prime numbers from their divisors, and so on. This is just one piece of code that will eventually become part of a larger program.