print(os.environ.keys()) should only print the keys

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2017-12-13.08:37:00.625>
labels = ['type-bug', 'library', '3.9', '3.10']
title = 'print(os.environ.keys()) should only print the keys'
updated_at = <Date 2020-11-06.19:11:50.449>
user = 'https://github.com/asmeurer'

bugs.python.org fields:

activity = <Date 2020-11-06.19:11:50.449>
actor = 'iritkatriel'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2017-12-13.08:37:00.625>
creator = 'Aaron.Meurer'
dependencies = []
files = []
hgrepos = []
issue_num = 32300
keywords = []
message_count = 20.0
messages = ['308190', '308199', '308200', '308219', '308220', '308223', '308241', '308244', '308249', '308251', '308266', '308309', '308314', '308315', '308321', '308334', '308335', '308338', '308357', '308358']
nosy_count = 6.0
nosy_names = ['rhettinger', 'vstinner', 'r.david.murray', 'Aaron.Meurer', 'serhiy.storchaka', 'cheryl.sabella']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue32300'
versions = ['Python 3.9', 'Python 3.10']