merge the underlying data stores of unicodedata and the str type

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2018-02-05.02:19:59.568>
labels = ['interpreter-core', 'type-feature', '3.9', 'expert-unicode']
title = 'merge the underlying data stores of unicodedata and the str type'
updated_at = <Date 2019-08-15.04:09:43.584>
user = 'https://github.com/benjaminp'

bugs.python.org fields:

activity = <Date 2019-08-15.04:09:43.584>
actor = 'Greg Price'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core', 'Unicode']
creation = <Date 2018-02-05.02:19:59.568>
creator = 'benjamin.peterson'
dependencies = []
files = []
hgrepos = []
issue_num = 32771
keywords = []
message_count = 11.0
messages = ['311634', '311655', '349546', '349547', '349614', '349616', '349629', '349650', '349670', '349784', '349791']
nosy_count = 6.0
nosy_names = ['vstinner', 'benjamin.peterson', 'mcepl', 'ezio.melotti', 'serhiy.storchaka', 'Greg Price']
pr_nums = []
priority = 'normal'
resolution = None
stage = 'needs patch'
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue32771'
versions = ['Python 3.9']