twisted-webclient

from twisted.web import client

from twisted.internet import reactor

import sys



def printPage(data):

    print data

    reactor.stop( )



def printError(failure):

    print >> sys.stderr, "Error:", failure.getErrorMessage( )

    reactor.stop( )



if len(sys.argv) == 2:

    url = sys.argv[1]

    client.getPage(url).addCallback(

        printPage).addErrback(

        printError)

    reactor.run( )

else:

    print "Usage: webcat.py <URL>"

   d = deferredFunction( )

    d.addCallback(resultHandler)

    d.addErrback(errorHandler)

can be expressed as:

    deferredFunction( ).addCallback(resultsHandler).addErrback(errorHandler)