primes.py

import sys
import math

def is_prime(n):
    if n < 4:
        return True
    if n % 2 == 0:
        return False
    for a in range(3, int(math.sqrt(n))+1):
        if n % a == 0:
            return False
    return True

def calculate_primes(n):
    "returns an array with n primes"
    primes = []
    p = 1
    for i in range(0, n):
        while not is_prime(p):
            p += 1
        primes.append(p)
        p += 1
    return primes

calculate_primes(int(sys.argv[1]))