Sieve of Eratosthenes Algorithm for Finding Prime Numbers

sum_primes.py

import math

def primeSieve(sieveSize):
     # Returns a list of prime numbers calculated using
     # the Sieve of Eratosthenes algorithm.
     sieve = [True] * sieveSize
     sieve[0] = False # zero and one are not prime numbers
     sieve[1] = False
     for i in range(2, int(math.sqrt(sieveSize)) + 1):
         pointer = i * 2
         while pointer < sieveSize:
             sieve[pointer] = False
             pointer += i
# compile the list of primes
     primes = []
     for i in range(sieveSize):
        if sieve[i] == True:
            primes.append(i)
     return primes

digits = primeSieve(2000000)

print(sum(digits))