merge heads

diff --cc Misc/NEWS
index 654a7a230e139efdbb5f365fd0219503f01b4ac0,6f2a8c8681c9accb22538e37bc3eaaa6f0390575..2fe06ed5b60acc7c374ab35e843ba300d46e07da
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -37,8 -30,10 +37,12 @@@ Core and Builtin
  - Issue #12546: Allow \x00 to be used as a fill character when using str, int,
    float, and complex __format__ methods.
  
 +- Issue #20480: Add ipaddress.reverse_pointer. Patch by Leon Weber.
 +
+ - Issue #13598: Modify string.Formatter to support auto-numbering of 
+   replacement fields. It now matches the behavior of str.format() in
+   this regard.
+ 
  Library
  -------