% ./python.exe -E -We -m test -v test_enum


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ERROR: test_custom_strenum_with_warning (test.test_enum.TestEnum)
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Traceback (most recent call last):
  File "/Users/iritkatriel/src/cpython-1/Lib/test/test_enum.py", line 2324, in test_custom_strenum_with_warning
    self.assertEqual(OkayEnum.one, '{}'.format(OkayEnum.one))
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/iritkatriel/src/cpython-1/Lib/enum.py", line 1006, in __format__
    warnings.warn(
    ^^^^^^^^^^^^^^
DeprecationWarning: in 3.12 format() will use the enum member, not the enum member's value;
use a format specifier, such as :d for an integer-based Enum, to maintain the current display

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