Use the py launcher in venv Windows examples

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2018-01-15.02:08:16.148>
labels = ['3.8', '3.9', '3.10', 'type-feature', 'OS-windows', 'docs']
title = 'Use the py launcher in venv Windows examples'
updated_at = <Date 2021-03-17.05:18:38.895>
user = 'https://bugs.python.org/pwatson'

bugs.python.org fields:

activity = <Date 2021-03-17.05:18:38.895>
actor = 'eryksun'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation', 'Windows']
creation = <Date 2018-01-15.02:08:16.148>
creator = 'pwatson'
dependencies = []
files = []
hgrepos = []
issue_num = 32553
keywords = []
message_count = 11.0
messages = ['309943', '309949', '310000', '310001', '310002', '310004', '310015', '310024', '310028', '310057', '310285']
nosy_count = 10.0
nosy_names = ['terry.reedy', 'paul.moore', 'tim.golden', 'ned.deily', 'docs@python', 'zach.ware', 'eryksun', 'steve.dower', 'pwatson', 'Mariatta']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue32553'
versions = ['Python 3.8', 'Python 3.9', 'Python 3.10']