Prime Number Tester

# prime_tester.py
#   This program accepts a n value as input and determines whether
#   or not it is prime.
# by: Scott Gordon

from math import sqrt


def is_prime(n):
    """Determines whether number (n) is prime or not"""
    if n % 2 == 0 and n != 2:
        return False
    factor = 3
    while factor <= sqrt(n):
        if n % factor == 0:
            return False
        factor += 2
    return True


def main():
    print("Prime Number Tester\n")
    n = int(input("Enter a number: "))
    if is_prime(n):
        print(f"{n} is prime.")
    else:
        print(f"{n} Is not prime.")


if __name__ == '__main__':
    main()