There is a fix from the upstream around enum.
https://github.com/boostorg/python/commit/a218babc8daee904a83f550fb66e5cb3f1cb3013 Fix enum_type_object type on Python 3.11 The enum_type_object type inherits from PyLong_Type which is not tracked by the GC. Instances doesn't have to be tracked by the GC: remove the Py_TPFLAGS_HAVE_GC flag. The Python C API documentation says: "To create a container type, the tp_flags field of the type object must include the Py_TPFLAGS_HAVE_GC and provide an implementation of the tp_traverse handler." https://docs.python.org/dev/c-api/gcsupport.html The new exception was introduced in Python 3.11 by: python/cpython#88429 an opinion ?
