Modules/signalmodule.c creates handlers for signals bounded by `NSIG`; requires fudging to support realtime signals, etc

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-02-05.22:15:07.671>
labels = ['interpreter-core', '3.8']
title = 'Modules/signalmodule.c creates handlers for signals bounded by `NSIG`; requires fudging to support realtime signals, etc'
updated_at = <Date 2020-02-06.17:48:15.443>
user = 'https://github.com/ngie-eign'

bugs.python.org fields:

activity = <Date 2020-02-06.17:48:15.443>
actor = 'ngie'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2020-02-05.22:15:07.671>
creator = 'ngie'
dependencies = []
files = []
hgrepos = []
issue_num = 39565
keywords = []
message_count = 1.0
messages = ['361458']
nosy_count = 1.0
nosy_names = ['ngie']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue39565'
versions = ['Python 3.8']