dataclass looks up field default value on the class, not the class's __dict__

GitHub fields:

assignee = 'https://github.com/ericvsmith'
closed_at = None
created_at = <Date 2021-06-17.12:34:23.449>
labels = ['type-bug', 'library', '3.9', '3.10', '3.11']
title = "dataclass looks up field default value on the class, not the class's __dict__"
updated_at = <Date 2021-06-17.14:07:17.550>
user = 'https://github.com/ericvsmith'

bugs.python.org fields:

activity = <Date 2021-06-17.14:07:17.550>
actor = 'eric.smith'
assignee = 'eric.smith'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-06-17.12:34:23.449>
creator = 'eric.smith'
dependencies = []
files = []
hgrepos = []
issue_num = 44443
keywords = []
message_count = 1.0
messages = ['396000']
nosy_count = 1.0
nosy_names = ['eric.smith']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue44443'
versions = ['Python 3.9', 'Python 3.10', 'Python 3.11']