Sieve of Eranthoses [Threaded] {WIP}

import datetime
import threading

thread_count=4

#sieve of eranthoses

#function to create intial sieve
def numList(upTo):
    primes = []
    for i in range(upTo):
        primes.append(True)
    return primes

primes=numList(10)

def dePrime(lower,upper,prime,num):
    i=lower+lower%prime
    global primes
    while i<upper:
        print(stg(num)+" "+str(i))
        primes[i]=False
        i=i+1

def thread_dePrime(num_threads,prime):
    global primes

    chunksize=int(len(primes)/num_threads)

    threads=[]

    for i in range(num_threads):
        if i==num_threads:
            threads.append(threading.Thread(target=dePrime, args=(chunksize * (i), len(primes), prime, i)))
        else:
            threads.append(threading.Thread(target=dePrime, args=(chunksize*(i),chunksize*(i+1),prime, i)))

    for i in range(num_threads):
        threads[i].start()

    for i in range(num_threads):
        threads[i].join()

#function to perform the sieving
def primeCalc(primes):
    primes[1] = False #1 is not prime
    prime_counter = 0 #intializing prime counter

    for i in range(len(primes)): #for loop to go through the array of numbers to test
        if i==0: #skip 0, count array from 1
            print("")
        else:
            if primes[i]: #if the ith element is true then this is a prime
                #print(str(i)+" is prime")
                thread_dePrime(thread_count,i)

    print(prime_counter)

startTime=datetime.datetime.now()

primeCalc(primes)

endTime=datetime.datetime.now()

print("------------------------")
print("Time to Commute: "+str(endTime-startTime))