Мультипроцессинг функции ( генератор комбинаций)

import random, time
 
def pass_gen():
    abc=list("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890")
    start_time = time.time()
    n = 8 # длинна комбинации
    m = 5000000 # количество комбинаций
    mas = []
    mas1 = ''
    with open('passwords.txt','w+') as f:
        for k in range(m):
            for i in range(n):
                mas.append(random.choice(abc))
            mas1 = ''.join(mas)
 
 
            f.write(mas1+'\n')
            mas.clear()
            mas1 = ''
 
    print("--- %s seconds ---" % (time.time() - start_time))
 
def main():
    pass_gen()
 
if __name__== '__main__':
    main()

import random, time
from multiprocessing import Pool
 
 
def pass_gen(ABC):
    abc = ABC
    """
    ABC=list("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
    nums=list("1234567890")
    common=[abc,ABC,nums]
    """
    start_time = time.time()
 
    n = 8
    m = 20000
    mas = []
    mas1 = ''
    mas2 = ''
    for k in range(m):
        for i in range(n):
            mas.append(random.choice(abc))
            mas1 = ''.join(mas)
    mas2 = mas1
    mas.clear()
    mas1 = ''
    print("--- %s seconds ---" % (time.time() - start_time))
    print(mas2)
    return mas2
 
 
 
 
def main():
    abc = list("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890")
    with Pool(10) as p:
 
        map(pass_gen,abc)
 
 
if __name__== '__main__':
    main()