from twisted.internet import defer, reactor from twisted.web.client import getPage def pageCallback(result): return len(result) def listCallback(result): print result def finish(ign): reactor.stop() def test(): d1 = getPage('http://www.google.com') d1.addCallback(pageCallback) d2 = getPage('http://yahoo.com') d2.addCallback(pageCallback) dl = defer.DeferredList([d1, d2]) dl.addCallback(listCallback) dl.addCallback(finish) test() reactor.run()