Importing the main module twice leads to two incompatible instances

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2016-07-24.15:46:17.645>
labels = ['interpreter-core', 'type-bug', '3.11']
title = 'Importing the main module twice leads to two incompatible instances'
updated_at = <Date 2021-06-15.17:37:28.937>
user = 'https://github.com/TheLastProject'

bugs.python.org fields:

activity = <Date 2021-06-15.17:37:28.937>
actor = 'iritkatriel'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2016-07-24.15:46:17.645>
creator = 'SylvieLorxu'
dependencies = []
files = ['43877']
hgrepos = []
issue_num = 27607
keywords = []
message_count = 14.0
messages = ['271164', '271184', '271185', '271188', '271189', '271195', '271196', '271210', '271211', '271217', '271243', '271248', '271253', '271264']
nosy_count = 7.0
nosy_names = ['rhettinger', 'cameron', 'r.david.murray', 'martin.panter', 'abarry', 'SylvieLorxu', 'Kwpolska']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue27607'
versions = ['Python 3.11']