Naive Primality Test in python

is_prime.py

import math

def smallest_div(n):
    if n <= 1:
        return 1
    return min(i for i in range(2, n + 1) if n % i == 0)


def check_prime(n):
    if n % 2 == 0:
        return smallest_div(n)

    r = math.sqrt(n)
    i = 3
    while i <= r:
        if n % i == 0:
            return smallest_div(n)
        i += 2

    return 1


def is_prime(n):
    if n <= 1:
        return smallest_div(n)
    if n == 2:
        return 1
    return check_prime(abs(int(n)))


print(is_prime(4))