Improve help() by making typing.overload() information accessible at runtime

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-09-04.18:03:28.637>
labels = ['3.11']
title = 'Improve help() by making typing.overload() information accessible at runtime'
updated_at = <Date 2022-03-28.22:36:21.459>
user = 'https://github.com/rhettinger'

bugs.python.org fields:

activity = <Date 2022-03-28.22:36:21.459>
actor = 'gvanrossum'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = []
creation = <Date 2021-09-04.18:03:28.637>
creator = 'rhettinger'
dependencies = []
files = []
hgrepos = []
issue_num = 45100
keywords = ['patch']
message_count = 14.0
messages = ['401052', '401074', '401080', '401094', '401097', '413677', '413678', '413684', '413685', '413695', '413751', '414561', '414566', '416226']
nosy_count = 9.0
nosy_names = ['gvanrossum', 'rhettinger', 'ronaldoussoren', 'JelleZijlstra', 'Spencer Brown', 'sobolevn', 'kj', 'AlexWaygood', 'DiddiLeija']
pr_nums = ['31716']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue45100'
versions = ['Python 3.11']