20190417

import time
import threading
def music(fun):
    for i in range(2):
        print('music')
        time.sleep(2)
        print('end the music')
def mover(func):
    for i in range(2):
        print('movers')
        time.sleep(8)
        print('end the movers')
# IO form --> sleep() blocking
Threads = []
t1 = threading.Thread(target=music,args=('qil',))
t2 = threading.Thread(target=mover,args=('xiu',))
Threads.append(t1)
Threads.append(t2)

begin = time.time()
for t in Threads:
    t.start()
t.join() # available
#t.join() # unavailable
# t2.start()
# t1.join()
# t2.join()
end = time.time()
print('combination',end-begin)

THE OUTPUT:

# t.join() is available
music
movers
end the music
music
end the music
end the movers
movers
end the movers
combination 16.012058973312378
#t.join() isn't available

music
movers
combination 0.0
end the music
music
end the movers
movers
end the music
end the movers