On Sat, Jul 7, 2012 at 10:23 AM, levi nie <levinie...@gmail.com> wrote: > my code: > > aList=[1,2,3,4,5,6,7,8,9,10] > xList=[1,2,3] > print "now aList is",aList.extend(xList) > > output: > now aList is None > > what i want is [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 1, 2, 3]
See http://stackoverflow.com/a/1682601 list.extend(), list.append(), etc. operate in-place, mutating the existing list object. Such methods return None to emphasize that they do not create new lists. Regards, Chris -- http://mail.python.org/mailman/listinfo/python-list
