Mock `_mock_wraps` is undocumented and inconsistently named

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-02-20.08:44:24.940>
labels = ['3.8', 'library']
title = 'Mock `_mock_wraps` is undocumented and inconsistently named'
updated_at = <Date 2021-02-27.02:33:48.709>
user = 'https://github.com/Woodz'

bugs.python.org fields:

activity = <Date 2021-02-27.02:33:48.709>
actor = 'terry.reedy'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-02-20.08:44:24.940>
creator = 'Woodz'
dependencies = []
files = []
hgrepos = []
issue_num = 43273
keywords = []
message_count = 2.0
messages = ['387397', '387760']
nosy_count = 2.0
nosy_names = ['terry.reedy', 'Woodz']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue43273'
versions = ['Python 3.8']