asdict/astuple Dataclass methods

GitHub fields:

assignee = 'https://github.com/ericvsmith'
closed_at = None
created_at = <Date 2019-04-18.20:31:10.914>
labels = ['3.8', 'type-feature', 'library']
title = 'asdict/astuple Dataclass methods'
updated_at = <Date 2019-04-19.10:53:51.428>
user = 'https://bugs.python.org/gsakkis'

bugs.python.org fields:

activity = <Date 2019-04-19.10:53:51.428>
actor = 'gsakkis'
assignee = 'eric.smith'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2019-04-18.20:31:10.914>
creator = 'gsakkis'
dependencies = []
files = []
hgrepos = []
issue_num = 36662
keywords = []
message_count = 4.0
messages = ['340511', '340523', '340532', '340537']
nosy_count = 5.0
nosy_names = ['rhettinger', 'gsakkis', 'eric.smith', 'matrixise', 'xtreak']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue36662'
versions = ['Python 3.8']