SF patch 1631942 by Collin Winter:

(a) "except E, V" -> "except E as V"
(b) V is now limited to a simple name (local variable)
(c) V is now deleted at the end of the except block

Lib/ConfigParser.py

@@ -567,7 +567,7 @@ class ConfigParser(RawConfigParser):
                 value = self._KEYCRE.sub(self._interpolation_replace, value)
                 try:
                     value = value % vars
-                except KeyError, e:
+                except KeyError as e:
                     raise InterpolationMissingOptionError(
                         option, section, rawval, e[0])
             else: