os.path.realpath() unexpected breaking change: resolves subst'd paths to real paths

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-04-28.16:26:16.087>
labels = ['3.8', 'type-bug', 'library', 'OS-windows']
title = "os.path.realpath() unexpected breaking change: resolves subst'd paths to real paths"
updated_at = <Date 2021-05-02.20:10:57.243>
user = 'https://bugs.python.org/sfmc'

bugs.python.org fields:

activity = <Date 2021-05-02.20:10:57.243>
actor = 'sfmc'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)', 'Windows']
creation = <Date 2021-04-28.16:26:16.087>
creator = 'sfmc'
dependencies = []
files = []
hgrepos = []
issue_num = 43968
keywords = []
message_count = 9.0
messages = ['392234', '392278', '392357', '392390', '392487', '392497', '392510', '392700', '392718']
nosy_count = 6.0
nosy_names = ['paul.moore', 'tim.golden', 'zach.ware', 'eryksun', 'steve.dower', 'sfmc']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue43968'
versions = ['Python 3.8']