http.client no longer sends HTTP request in one TCP package

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2018-03-13.12:06:43.935>
labels = ['3.7', '3.8', 'type-bug', 'library']
title = 'http.client no longer sends HTTP request in one TCP package'
updated_at = <Date 2018-03-13.17:40:23.187>
user = 'https://github.com/tiran'

bugs.python.org fields:

activity = <Date 2018-03-13.17:40:23.187>
actor = 'orsenthil'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2018-03-13.12:06:43.935>
creator = 'christian.heimes'
dependencies = []
files = []
hgrepos = []
issue_num = 33067
keywords = ['3.5regression']
message_count = 1.0
messages = ['313743']
nosy_count = 3.0
nosy_names = ['orsenthil', 'christian.heimes', 'benjamin.peterson']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue33067'
versions = ['Python 3.6', 'Python 3.7', 'Python 3.8']