import _thread
import time
import sys
sys.setswitchinterval(1000)

def countdown(n,lck):
    while n > 0:
         n = n - 1
    lck.release()     # Signal termination

lck_1 = _thread.allocate_lock()
lck_2 = _thread.allocate_lock()
lck_1.acquire()
lck_2.acquire()
start = time.time()
_thread.start_new_thread(countdown,(5000000,lck_1))
_thread.start_new_thread(countdown,(5000000,lck_2))
lck_1.acquire()      # Wait for termination
lck_2.acquire()
end = time.time()
k = end - start
print(k)