is_simple_int.py

import math

def is_simple_number(n):
    if n < 2:
        return False
    elif n == 2:
        return True
    elif n % 2 == 0:
        return False
    else:
        for i in range(3, int(math.sqrt(n))+1, 2):
            if n % i == 0:
                return False
        return True
    
print(is_simple_number(1))  # False
print(is_simple_number(0))  # False
print(is_simple_number(2)) # True
print(is_simple_number(13)) # True