Faster way to list primes in Python

pythonprimes

def listprimes2(m):
    '''another attempt to list all primes below m'''
    values = range(m+1) #note that in this list the key and the value are the same.
    primes = values[:]
    primes[1] = 0 #1 doesn't count as a prime
    for i in values:
        if primes[i] == 0:
            pass
        else:
            for j in values[i+1:]:
                if primes[j]==0 or primes[j]%i != 0:
                    pass
                else:
                    primes[j] = 0
    return primes

    
import time
tstart = time.time()
ans = sum(listprimes2(2000000))
telapsed = time.time()-tstart

It took about 37 seconds to execute. I know it's not perfect, but at least got the right answer.

thanks John!