multiprocessing - Join two process by pid in Python -

i created 2 process using fork in python as

import os import sys pid = os.fork() if pid > 0:    # set variable ( lets setting_a )    # lets execute    os.waitpid(pid,0) else:    pid = os.fork()    if pid > 0:       # set other variable ( lets setting_b )       # let execute       os.waitpid(pid, 0)    else:       sys.exit(0) # common workflow 

problem:

lets assume script run setting_a takes 10 sec. while same script run setting_b takes 2 min. want run 2 instances of script 2 different setting in parallel. make sure parent process wait child finish, used os.waitpid(), made sequential execution. run first setting b , a. how can maintain parallelism , parent process wait until child process finish. tried searching join() process() class in python. there way can join these process pid without affecting change.