Nested coroutines

test.py

from tornado import gen, ioloop
from tornado.httpclient import AsyncHTTPClient

@gen.coroutine
def worker():
    sites = ['http://google.com', 'http://clarin.com', 'http://lanacion.com']
    
    @gen.coroutine
    def _bulk():
        if not sites:
            raise gen.Return(False)
        site = sites.pop()
        response = yield AsyncHTTPClient().fetch(site)
        print 'Code(%s): %s' % (response.code, site)
        raise gen.Return(True)
        
    while True:
        result = yield _bulk()
        if not result:
            break

    raise gen.Return(sites)
        

@gen.coroutine
def run():
    try:
        x = yield worker()
        print x
    except Exception, e:
        print e
    ioloop.IOLoop.instance().stop()


if __name__ == '__main__':
    run()
    ioloop.IOLoop.instance().start()