python yield的用法

#coding=utf-8
from time import sleep

def test(l1):
    for l in l1:
        print l
        sleep(5)
        yield ‘result:%s‘ % l

l1=[1,2,3,4,5]
t=test(l1=l1)
for l in l1:
    print t.next()

#coding=utf-8
from time import sleep

def test():
    get=‘‘
    while True:
        l = yield get
        if l:
            print l
            sleep(2)
            get= ‘result:%s‘ % l
        else:
            return

l1=[1,2,3,4,5]
t=test()
t.send(None)
for l in l1:
    r= t.send(str(l))
    print r