def fib(max):

    n,a,b = 0,0,1

    while n < max:

        #print(b)

        yield b

        a,b = b,a+b

        n= n+1

    return 'done'

g = fib(10)

while True:

    try:

        x = g.__next__()

        print('g:',x)

    except StopIteration as e:

        print('Generator return value:',e.value)

        break

import time

def consumer(name):

    print('[%s] prepare to eat baozi!!'%name)

    while True:

        baozi = yield

        print('baozi [%s] is coming,ate by [%s]'%(baozi,name))

def producer(name):

    c = consumer('A')

    c2 = consumer('B')

    c.__next__()

    c2.__next__()

    print('start'.center(30,'-'))

    for i in range(10):

        time.sleep(1)

        print('just one,half to half')

        c.send(i)

        c2.send(i)

producer('wt')