from multiprocessing import process  def print_numbers():     for i in range(5):         print(i)  p = process(target=print_numbers) p.start()  # starts a new process p.join()   # waits for the process to finish 

p = process(target=print_numbers) p.start()  # runs the target function in a separate process 

p = process(target=print_numbers) p.start() p.join(2)  # waits up to 2 seconds for the process to finish 

p = process(target=print_numbers) p.start() print(p.is_alive())  # true if the process is still running 

from multiprocessing import current_process  def print_current_process():     print(current_process())  p = process(target=print_current_process) p.start()  # prints the current process info 

p1 = process(target=print_numbers) p2 = process(target=print_numbers) p1.start() p2.start()  print(process.active_children())  # lists all active child processes 

from multiprocessing import cpu_count  print(cpu_count())  # returns the number of cpus on the machine 

from multiprocessing import pool  def square(n):     return n * n  with pool(4) as pool:  # pool with 4 worker processes     result = pool.map(square, [1, 2, 3, 4, 5])  print(result)  # [1, 4, 9, 16, 25] 

from multiprocessing import process, queue  def put_data(q):     q.put([1, 2, 3])  def get_data(q):     data = q.get()     print(data)  q = queue() p1 = process(target=put_data, args=(q,)) p2 = process(target=get_data, args=(q,))  p1.start() p2.start() p1.join() p2.join() 

from multiprocessing import process, lock  lock = lock()  def print_numbers():     with lock:         for i in range(5):             print(i)  p1 = process(target=print_numbers) p2 = process(target=print_numbers)  p1.start() p2.start() p1.join() p2.join() 

from multiprocessing import process, value  def increment(val):     with val.get_lock():         val.value += 1  shared_val = value('i', 0) processes = [process(target=increment, args=(shared_val,)) for _ in range(10)]  for p in processes:     p.start()  for p in processes:     p.join()  print(shared_val.value)  # output will be 10 

from multiprocessing import process, pipe  def send_message(conn):     conn.send("hello from child")     conn.close()  parent_conn, child_conn = pipe() p = process(target=send_message, args=(child_conn,)) p.start()  print(parent_conn.recv())  # receives data from the child process p.join() 

from multiprocessing import process, manager  def modify_list(shared_list):     shared_list.append("new item")  with manager() as manager:     shared_list = manager.list([1, 2, 3])      p = process(target=modify_list, args=(shared_list,))     p.start()     p.join()      print(shared_list)  # [1, 2, 3, "new item"] 

from multiprocessing import Process, Semaphore import time  sem = Semaphore(2)  # Only 2 processes can access the resource  def limited_access():     with sem:         print("Accessing resource")         time.sleep(2)  processes = [Process(target=limited_access) for _ in range(5)]  for p in processes:     p.start()  for p in processes:     p.join()