from threading import Thread, currentThread
import time
import itertools

COUNT = 10000000
items = []
def count(n):
    name = currentThread().name
    while n > 0:
        n -= 1
        items.append(name)

t1 = Thread(target=count,args=(COUNT,))
t2 = Thread(target=count,args=(COUNT,))
t3 = Thread(target=count,args=(COUNT,))
t1.start(); t2.start(); t3.start()
t1.join(); t2.join(); t3.join()

# Output a condensed trace showing thread scheduling
for key, seq in itertools.groupby(items):
    print("%s %s" % (key, len(list(seq))))