concurrent.futures.ProcessPoolExecutor is unable to forward exceptions with state.

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-12-28.16:37:04.784>
labels = ['type-bug', 'library', '3.9']
title = 'concurrent.futures.ProcessPoolExecutor is unable to forward exceptions with state.'
updated_at = <Date 2020-12-28.16:37:04.784>
user = 'https://bugs.python.org/damienlevac'

bugs.python.org fields:

activity = <Date 2020-12-28.16:37:04.784>
actor = 'damien.levac'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2020-12-28.16:37:04.784>
creator = 'damien.levac'
dependencies = []
files = ['49703']
hgrepos = []
issue_num = 42769
keywords = []
message_count = 1.0
messages = ['383903']
nosy_count = 1.0
nosy_names = ['damien.levac']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue42769'
versions = ['Python 3.9']