Martin Panter added the comment: For what it’s worth, every now and then I have to stop and remember that I can’t do this sort of thing:
unsupported_keys = config_dict.keys().difference(supported_list) though it is not a big problem to rewrite it as unsupported_keys = config_dict.keys() - set(supported_list) Also it looks like one can already effectively do x.copy() using the existing immutable Set operators, so that worm can is already opened: >>> ListBasedSet("abc") & ListBasedSet("abc") <__main__.ListBasedSet object at 0x7f419951b860> On the other hand, a matching almost equivalent operator does exist for a.issubset(b): a <= b, or a.__le__(b). ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue23161> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com