Make modules picklable

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-02-01.19:17:44.942>
labels = ['type-feature', 'library']
title = 'Make modules picklable'
updated_at = <Date 2021-08-22.00:01:47.262>
user = 'https://github.com/Arusekk'

bugs.python.org fields:

activity = <Date 2021-08-22.00:01:47.262>
actor = 'LeMyst'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-02-01.19:17:44.942>
creator = 'Arusekk'
dependencies = []
files = []
hgrepos = []
issue_num = 43093
keywords = []
message_count = 3.0
messages = ['386090', '386096', '399963']
nosy_count = 3.0
nosy_names = ['Arusekk', 'MegaIng', 'LeMyst']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue43093'
versions = []