Python 3 preparation: update calls to dict methods. Tool-assisted patch. Changes of iterkeys / itervalues / iteritems to keys / values / items are fully automated, but may make things less efficient in Python 2. Automated tools want to add list() around many calls to keys / values / items, but I thought most such list() additions were unnecessary because it seemed the result of keys / values / items was just iterated over while the set of dict keys remained unchanged, rather than used in a way requiring an actual list, or used while the set of keys in the dict could change. It's quite possible I missed some cases where list() was really needed, or left in some unnecessary list() calls. In cases where list() was only needed because the resulting list was then sorted in-place, I changed the code to use calls to sorted().

--- a/roundup/cgi/form_parser.py	Tue Jul 24 23:03:35 2018 +0000
+++ b/roundup/cgi/form_parser.py	Tue Jul 24 23:04:42 2018 +0000
@@ -589,7 +589,7 @@
         # property to be created. When editing a FileClass node, it should
         # either have a non-empty content property or no property at all. In
         # the latter case, nothing will change.
-        for (cn, id), props in all_props.items():
+        for (cn, id), props in list(all_props.items()):
             if id is not None and id.startswith('-') and not props:
                 # new item (any class) with no content - ignore
                 del all_props[(cn, id)]