python spawn python process code example

Example 1: worker pool model with multiprocessing

from multiprocessing import Pool

def f(x):
    return x*x

if __name__ == '__main__':
    with Pool(5) as p:
        print(p.map(f, [1, 2, 3]))

Example 2: python write subprocess stdout stderr to file

with open("stdout.txt","wb") as out, open("stderr.txt","wb") as err:
    subprocess.Popen("ls",stdout=out,stderr=err)