spec_set/autospec/spec seems to not be reading attributes defined in class body

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-06-04.14:28:47.540>
labels = ['3.8', 'type-bug', 'library', '3.9']
title = 'spec_set/autospec/spec seems to not be reading attributes defined in class body'
updated_at = <Date 2020-10-06.07:17:47.412>
user = 'https://github.com/efagerberg'

bugs.python.org fields:

activity = <Date 2020-10-06.07:17:47.412>
actor = 'xtreak'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2020-06-04.14:28:47.540>
creator = 'efagerberg'
dependencies = []
files = []
hgrepos = []
issue_num = 40864
keywords = ['patch']
message_count = 5.0
messages = ['370712', '370713', '370752', '370865', '378076']
nosy_count = 6.0
nosy_names = ['cjw296', 'michael.foord', 'lisroach', 'mariocj89', 'xtreak', 'efagerberg']
pr_nums = ['22572']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue40864'
versions = ['Python 3.6', 'Python 3.8', 'Python 3.9']