Support TLS Encrypted ClientHello (ECH)

GitHub fields:

assignee = 'https://github.com/tiran'
closed_at = None
created_at = <Date 2021-10-22.08:59:46.592>
labels = ['expert-SSL', 'type-feature']
title = 'Support TLS Encrypted ClientHello (ECH)'
updated_at = <Date 2021-11-02.15:51:37.975>
user = 'https://github.com/eighthave'

bugs.python.org fields:

activity = <Date 2021-11-02.15:51:37.975>
actor = 'eighthave'
assignee = 'christian.heimes'
closed = False
closed_date = None
closer = None
components = ['SSL']
creation = <Date 2021-10-22.08:59:46.592>
creator = 'eighthave'
dependencies = []
files = []
hgrepos = []
issue_num = 45567
keywords = []
message_count = 3.0
messages = ['404732', '404749', '405513']
nosy_count = 2.0
nosy_names = ['christian.heimes', 'eighthave']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue45567'
versions = []