Document pickle behavior for subclasses of dicts/lists #48962

assignee = None
closed_at = None
created_at = <Date 2008-12-21.17:24:03.973>
labels = ['easy', 'type-bug', 'docs']
title = 'Document pickle behavior for subclasses of dicts/lists'
updated_at = <Date 2015-11-26.22:11:25.100>
user = 'https://github.com/birkenfeld'

activity = <Date 2015-11-26.22:11:25.100>
actor = 'serhiy.storchaka'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation']
creation = <Date 2008-12-21.17:24:03.973>
creator = 'georg.brandl'
dependencies = ['3635']
files = []
hgrepos = []
issue_num = 4712
keywords = ['easy']
message_count = 4.0
messages = ['78154', '83098', '255434', '255439']
nosy_count = 7.0
nosy_names = ['georg.brandl', 'rhettinger', 'pitrou', 'alexandre.vassalotti', 'aronacher', 'eric.snow', 'serhiy.storchaka']
pr_nums = []
priority = 'normal'
resolution = None
stage = 'needs patch'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue4712'
versions = ['Python 2.7', 'Python 3.4', 'Python 3.5', 'Python 3.6']