Tutorial links to file object methods are broken.

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2017-01-06.09:58:43.773>
labels = ['type-bug', '3.7', 'docs']
title = 'Tutorial links to file object methods are broken.'
updated_at = <Date 2017-01-06.20:47:31.474>
user = 'https://github.com/JonathanRoach'

bugs.python.org fields:

activity = <Date 2017-01-06.20:47:31.474>
actor = 'jonroach@icloud.com'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation']
creation = <Date 2017-01-06.09:58:43.773>
creator = 'jonroach@icloud.com'
dependencies = []
files = []
hgrepos = []
issue_num = 29175
keywords = []
message_count = 3.0
messages = ['284806', '284825', '284848']
nosy_count = 6.0
nosy_names = ['georg.brandl', 'ezio.melotti', 'eric.araujo', 'r.david.murray', 'docs@python', 'jonroach@icloud.com']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue29175'
versions = ['Python 3.6', 'Python 3.7']