Documentation for handling of non-type metaclass hints is unclear

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2016-10-13.23:50:59.803>
labels = ['type-bug', 'library', 'docs']
title = 'Documentation for handling of non-type metaclass hints is unclear'
updated_at = <Date 2016-10-16.07:49:51.930>
user = 'https://github.com/NeilGirdhar'

bugs.python.org fields:

activity = <Date 2016-10-16.07:49:51.930>
actor = 'ncoghlan'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation', 'Library (Lib)']
creation = <Date 2016-10-13.23:50:59.803>
creator = 'NeilGirdhar'
dependencies = []
files = []
hgrepos = []
issue_num = 28437
keywords = []
message_count = 14.0
messages = ['278625', '278627', '278704', '278705', '278706', '278727', '278728', '278729', '278743', '278744', '278745', '278746', '278747', '278748']
nosy_count = 3.0
nosy_names = ['ncoghlan', 'docs@python', 'NeilGirdhar']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue28437'
versions = ['Python 3.6']