fix problem with bounce-message if incoming mail has insufficient privilege... ...e.g., user not existing (issue 2550534) Added a regression test for this issue that reproduces the traceback reported in issue 2550534 I'm using a slightly modified variant of the original patch that avoids repeated string-concatenation (which could degenerate to quadratic runtime behaviour for large number of email headers).

"""
roundup.anypy - compatibility layer for any Python 2.3+
"""
VERSION = '.'.join(map(str,
                       (0,
                        1,  # hashlib_, sets_
                        )))