David did and does a great job (many thanks to him), but surprisingly many of changes from msg205005 are still not mentioned in What's New.

Improvements and changes in modules:

aifc:  Any bytes-like objects are now accepted.

audioop:  Any bytes-like objects are now accepted.  Strings no more supported.

base64:  ascii85/base85 codecs.

codecs:  The cp1125 encoding.

collections:  New optional parameter in ChainMap.new_child().

dbm:  Support for the context management protocol.

dis:  Added the stack_effect() function.

email:  The policy keyword argument was added in email.message.Message 
constructor. The replace keyword argument was added in the set_param() 
method. 
The EmailPolicy.content_manager attribute was added 

filecmp:  Added the dircmp.DEFAULT_IGNORES  attribute.

functools:  total_ordering now supports the NotImplemented value.

glob:  Added the escape() function.

ipaddress:  Added the IPv4Address.is_global attribute.

json:  Used ``(',', ': ')`` as default in dump() and dumps() if indent is not 
None. I.e. trailing spaces no more produced by default.

logging:  An instance of a subclass of RawConfigParser is now accepted as a 
value for fname in the fileConfig() function. The verify argument was added in 
the listen() function.

multiprocessing:  Added following functions: get_all_start_methods(), 
get_context(), get_start_method(), and set_start_method(). set_executable() 
is now supported on Unix when the 'spawn' start method is used. Added the 
context parameter in Pool constructor.

operator:  Added the length_hint() function.

os:  Add O_TMPFILE constant on Linux.

plistlib:  Deprecated readPlist(), writePlist() readPlistFromBytes(), 
and writePlistToBytes() functions, the Data class.

shutil:  Added the SameFileError exception.

sunau:  Added support for 24-bit samples. Any bytes-like objects are now 
accepted.

sys:  Added the __interactivehook__ 
hook.

tarfile:  Added command-line interface.

urllib:  Added the HTTPError.headers attribute. Added the Request.full_url 
attribute and the Request.remove_header() and Request.get_full_url() methods.

venv:  Added the ``with_pip`` parameter in EnvBuilder.

wave:  Any bytes-like objects are now accepted. Added support for unseekable 
files.

zipfile:  ZIP64 extensions are enabled by default.


Deprecations:

The 'U' mode in open() for file objects, in the fileinput and zipfile modules. A couple of plistlib functions. The html argument of XMLParser() and the parser argument of iterparse() in the xml.etree.elementtree module.