Nested lambdas in setattr() lose context in Python 2.7

[VictorLiu]

BPO	29101
Nosy	@benjaminp
Files	bug.py

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2016-12-29.04:25:25.583>
created_at = <Date 2016-12-29.03:58:24.094>
labels = ['type-bug', 'invalid']
title = 'Nested lambdas in setattr() lose context in Python 2.7'
updated_at = <Date 2016-12-29.04:25:25.581>
user = 'https://bugs.python.org/VictorLiu'

bugs.python.org fields:

activity = <Date 2016-12-29.04:25:25.581>
actor = 'benjamin.peterson'
assignee = 'none'
closed = True
closed_date = <Date 2016-12-29.04:25:25.583>
closer = 'benjamin.peterson'
components = []
creation = <Date 2016-12-29.03:58:24.094>
creator = 'Victor Liu'
dependencies = []
files = ['46069']
hgrepos = []
issue_num = 29101
keywords = []
message_count = 2.0
messages = ['284224', '284228']
nosy_count = 2.0
nosy_names = ['benjamin.peterson', 'Victor Liu']
pr_nums = []
priority = 'normal'
resolution = 'not a bug'
stage = None
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue29101'
versions = ['Python 2.7']

[VictorLiu]

I would expect bug.py to output:
foo
bar
baz

but instead we observe:
baz
baz
baz

Replicated on Windows 10 Home Edition, Python 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:42:59) [MSC v.1500 32 bit (Intel)]

[benjaminp]

https://docs.python.org/2/faq/programming.html#why-do-lambdas-defined-in-a-loop-with-different-values-all-return-the-same-result