Thanks for your reply Simon. I will read the article you told me to but first, please, have a look at this snippet:
>>> m = [2,3,4] >>> p = ['a','b','c'] >>> q = [m,p] >>> q [[2, 3, 4, 'a', 'b', 'c'], ['a', 'b', 'c']] >>> del p >>> q [[2, 3, 4, 'a', 'b', 'c'], ['a', 'b', 'c']] >>> How come q is not updated after I deleted p? This is my point. -- http://mail.python.org/mailman/listinfo/python-list