def create_primes_1(max_n):
    """ creating primes up to a maximum value. The even numbers are not
        touched. The primes itself are used to check for possible division. """
    primes = []
    for val in range(3, max_n+1, 2):
        found = False
        for divisor in primes:
            if val % divisor == 0:
                found = True
                break

        if not found:
            primes.append(val)
    return [2] + primes
 creating primes up to a maximum value. The even numbers are not
        touched. The primes itself are used to check for possible division. 
recipes/Python/577329_Some_prime_generation_algorithms/recipe-577329.py