bpo-43945: [Enum] reduce scope of new format() behavior (GH-26752)

* [Enum] reduce scope of new format behavior

Instead of treating all Enums the same for format(), only user mixed-in
enums will be affected.  In other words, IntEnum and IntFlag will not be
changing the format() behavior, due to the requirement that they be
drop-in replacements of existing integer constants.

If a user creates their own integer-based enum, then the new behavior
will apply:

    class Grades(int, Enum):
        A = 5
        B = 4
        C = 3
        D = 2
        F = 0

Now:  format(Grades.B)  -> DeprecationWarning and '4'
3.12:                   -> no warning, and 'B'

1 files changed, 2 insertions, 2 deletions

diff --git a/Lib/test/test_httpservers.py b/Lib/test/test_httpservers.py
index cb0a3aa..aeea020 100644
--- a/Lib/test/test_httpservers.py
+++ b/Lib/test/test_httpservers.py
@@ -259,7 +259,7 @@ class BaseHTTPServerTestCase(BaseTestCase):
         for code in (HTTPStatus.NO_CONTENT, HTTPStatus.NOT_MODIFIED,
                      HTTPStatus.PROCESSING, HTTPStatus.RESET_CONTENT,
                      HTTPStatus.SWITCHING_PROTOCOLS):
-            self.con.request('SEND_ERROR', '/{:d}'.format(code))
+            self.con.request('SEND_ERROR', '/{}'.format(code))
             res = self.con.getresponse()
             self.assertEqual(code, res.status)
             self.assertEqual(None, res.getheader('Content-Length'))
@@ -276,7 +276,7 @@ class BaseHTTPServerTestCase(BaseTestCase):
         for code in (HTTPStatus.OK, HTTPStatus.NO_CONTENT,
                      HTTPStatus.NOT_MODIFIED, HTTPStatus.RESET_CONTENT,
                      HTTPStatus.SWITCHING_PROTOCOLS):
-            self.con.request('HEAD', '/{:d}'.format(code))
+            self.con.request('HEAD', '/{}'.format(code))
             res = self.con.getresponse()
             self.assertEqual(code, res.status)
             if code == HTTPStatus.OK: