Overlapping PYTHONPATH may cause import already imported module

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2022-02-20.12:34:47.401>
labels = ['interpreter-core', 'type-bug', '3.8', '3.9', '3.10', '3.7']
title = 'Overlapping PYTHONPATH may cause import already imported module'
updated_at = <Date 2022-02-27.10:45:32.995>
user = 'https://github.com/aklajnert'

bugs.python.org fields:

activity = <Date 2022-02-27.10:45:32.995>
actor = 'aklajnert'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2022-02-20.12:34:47.401>
creator = 'aklajnert'
dependencies = []
files = []
hgrepos = []
issue_num = 46806
keywords = []
message_count = 7.0
messages = ['413584', '413713', '413714', '413716', '413772', '413813', '414146']
nosy_count = 3.0
nosy_names = ['docs@python', 'eric.snow', 'aklajnert']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue46806'
versions = ['Python 3.7', 'Python 3.8', 'Python 3.9', 'Python 3.10']