from math import sqrt
import time

def prime(n):
    if n<2: return False
    if n==2: return True
    return all(n%i for i in [2] + range(3, int(sqrt(n))+1, 2))

# return all primes up to n, fast as hell
def get_primes(n):
    numbers = range(3, n+1, 2)
    half = n//2
    current = 4

    for step in xrange(3, n+1, 2):
        for i in xrange(current, half, step):
            numbers[i-1]=0
        current += 2*(step+1)

        if current > half:
            p = [2] + filter(None, numbers)
            if not prime(n):
                try: p.remove(n)
                except ValueError: pass
            return p

start_time = time.time()
print(sum(get_primes(2000000)))
print("--- %s seconds ---" % (time.time() - start_time))