multithreading in python not working as expected -

import threading import time  def test1():  print "hello"  time.sleep(15)  print "hello2"   def test2():  print "hi"  th1 =threading.thread(test1()) th2 =threading.thread(test2())  p=[th1,th2] in p:  i.start()  in p:  i.join() 

i not sure if right, please correct me if not. expecting output printed in order hello hi , hello2. expecting 2 threads created run parallely . getting below output, hello hello2 , hi. thread2 running after completion of thread1. doing wrong? or understanding or threading wrong?

you need pass function reference thread() class constructor takes "keyword argument" called target (default: none).

passing result of function call (such you've done) have undesired behaviour since first argument thread() group=none.

example: (corrected)

import threading import time   def test1():     print "hello"     time.sleep(15)     print "hello2"   def test2():     print "hi"  th1 = threading.thread(target=test1) th2 = threading.thread(target=test2)  p = [th1, th2] in p:     i.start()  in p:     i.join() 

output:

$ python foo.py hello hi # 15s delay hello2 

see: threading.thread()

specifically:

class threading.thread(group=none, target=none, name=none, args=(), kwargs={})

this constructor should called keyword arguments.