unittest's assertRaises removes locals from tracebacks

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-02-26.22:01:11.668>
labels = ['3.8', '3.7', 'library', '3.9']
title = "unittest's assertRaises removes locals from tracebacks"
updated_at = <Date 2021-05-11.13:38:40.113>
user = 'https://github.com/blueyed'

bugs.python.org fields:

activity = <Date 2021-05-11.13:38:40.113>
actor = 'jacksonriley'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2020-02-26.22:01:11.668>
creator = 'blueyed'
dependencies = []
files = []
hgrepos = []
issue_num = 39766
keywords = []
message_count = 3.0
messages = ['362744', '362753', '393457']
nosy_count = 2.0
nosy_names = ['blueyed', 'jacksonriley']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = None
url = 'https://bugs.python.org/issue39766'
versions = ['Python 3.5', 'Python 3.6', 'Python 3.7', 'Python 3.8', 'Python 3.9']