Bad proxy returned immediately after BaseManager server restarted

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-10-26.09:17:38.074>
labels = ['3.8', 'library', '3.9']
title = 'Bad proxy returned immediately after BaseManager server restarted'
updated_at = <Date 2020-10-26.09:17:38.074>
user = 'https://bugs.python.org/jryan'

bugs.python.org fields:

activity = <Date 2020-10-26.09:17:38.074>
actor = 'jryan'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2020-10-26.09:17:38.074>
creator = 'jryan'
dependencies = []
files = []
hgrepos = []
issue_num = 42154
keywords = []
message_count = 1.0
messages = ['379657']
nosy_count = 1.0
nosy_names = ['jryan']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue42154'
versions = ['Python 3.8', 'Python 3.9']