Document the two changes to the mailbox.py module:

- All constructors grow an optional argument `factory' which is a
  callable used when new message instances are created by the next()
  methods.  Defaults to the rfc822.Message class.

- A new subclass of UnixMailbox is added, called PortableUnixMailbox.
  It's identical to UnixMailbox, but uses a more portable test for
  From_ delimiter lines.  With PortableUnixMailbox, any line that
  starts with "From " is considered a delimiter (this should really
  check for two newlines before the F, but it doesn't.

1 files changed, 7 insertions, 0 deletions

diff --git a/Misc/NEWS b/Misc/NEWS
index 2b9bb66..5c633f0 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -15,6 +15,13 @@ Core language, builtins, and interpreter
 
 Standard library
 
+- mailbox.py now has a new class, PortableUnixMailbox which is
+  identical to UnixMailbox but uses a more portable scheme for
+  determining From_ separators.  Also, the constructors for all the
+  classes in this module have a new optional `factory' argument, which
+  is a callable used when new message classes must be instantiated by
+  the next() method.
+
 - random.py is now self-contained, and offers all the functionality of
   the now-deprecated whrandom.py.  See the docs for details.  random.py
   also supports new functions getstate() and setstate(), for saving