bpo-40066: [Enum] update str() and format() output (GH-30582)

Undo rejected PEP-663 changes:

- restore `repr()` to its 3.10 status
- restore `str()` to its 3.10 status

New changes:

- `IntEnum` and `IntFlag` now leave `__str__` as the original `int.__str__` so that str() and format() return the same result
- zero-valued flags without a name have a slightly changed repr(), e.g. `repr(Color(0)) == '<Color: 0>'`
- update `dir()` for mixed-in types to return all the methods and attributes of the mixed-in type
- added `_numeric_repr_` to `Flag` to control display of unnamed values
- enums without doc strings have a more comprehensive doc string added
- `ReprEnum` added -- inheriting from this makes it so only `__repr__` is replaced, not `__str__` nor `__format__`; `IntEnum`, `IntFlag`, and `StrEnum` all inherit from `ReprEnum`

1 files changed, 2 insertions, 2 deletions

diff --git a/Doc/library/ssl.rst b/Doc/library/ssl.rst
index eb33d7e..4d8488a 100644
--- a/Doc/library/ssl.rst
+++ b/Doc/library/ssl.rst
@@ -2070,7 +2070,7 @@ to speed up repeated connections from the same clients.
       :attr:`SSLContext.verify_flags` returns :class:`VerifyFlags` flags:
 
          >>> ssl.create_default_context().verify_flags  # doctest: +SKIP
-         ssl.VERIFY_X509_TRUSTED_FIRST
+         <VerifyFlags.VERIFY_X509_TRUSTED_FIRST: 32768>
 
 .. attribute:: SSLContext.verify_mode
 
@@ -2082,7 +2082,7 @@ to speed up repeated connections from the same clients.
       :attr:`SSLContext.verify_mode` returns :class:`VerifyMode` enum:
 
          >>> ssl.create_default_context().verify_mode
-         ssl.CERT_REQUIRED
+         <VerifyMode.CERT_REQUIRED: 2>
 
 .. index:: single: certificates