In <344c23f8-f440-4c23-a5e6-9f93b0145...@googlegroups.com> Ho Yeung Lee <jobmatt...@gmail.com> writes:
> I find that list can not be key in dictionary > then find tuple can be as key > but when I add new tuple as key , got error in python 2.7 > groupkey = {(0,0): []} > groupkey[tuple([0,3])] = groupkey[tuple([0,3])] + [[0,1]] The right-hand side of your expression is rightly complaining that groupkey[(0,3)] doesn't exist. Would you expect to say a = a + 1 When a doesn't exist? Your code tries to do much the same thing. -- John Gordon A is for Amy, who fell down the stairs gor...@panix.com B is for Basil, assaulted by bears -- Edward Gorey, "The Gashlycrumb Tinies" -- https://mail.python.org/mailman/listinfo/python-list