t = walltime()
while True:
    tm = int(walltime(t))
    s = tm%60
    tm  = (tm-s)//60
    m = tm%60
    h = (tm - m)//60
    smc.clear()
    print "%s:%s:%s"%(h,m,s)
    sys.stdout.flush()
    sleep(5)

walltime(t)/60.