bpo-40066: Enum: modify `repr()` and `str()` (GH-22392)

* Enum: streamline repr() and str(); improve docs

- repr() is now ``enum_class.member_name``
- stdlib global enums are ``module_name.member_name``
- str() is now ``member_name``
- add HOW-TO section for ``Enum``
- change main documentation to be an API reference

1 files changed, 8 insertions, 0 deletions

diff --git a/Doc/whatsnew/3.10.rst b/Doc/whatsnew/3.10.rst
index e09cfb4..ea2834b 100644
--- a/Doc/whatsnew/3.10.rst
+++ b/Doc/whatsnew/3.10.rst
@@ -716,6 +716,14 @@ encodings
 :func:`encodings.normalize_encoding` now ignores non-ASCII characters.
 (Contributed by Hai Shi in :issue:`39337`.)
 
+enum
+----
+
+:class:`Enum` :func:`__repr__` now returns ``enum_name.member_name`` and
+:func:`__str__` now returns ``member_name``.  Stdlib enums available as
+module constants have a :func:`repr` of ``module_name.member_name``.
+(Contributed by Ethan Furman in :issue:`40066`.)
+
 gc
 --