не могу установить pip: "cannot import name 'PackageFinder' from 'pip._internal.index'"

На команду: py -m pip install -U pip

Выдает:

Traceback (most recent call last):
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\runpy.py", line 193, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\__main__.py", line 16, in <module>
    from pip._internal import main as _main  # isort:skip # noqa
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\__init__.py", line 40, in <module>
    from pip._internal.cli.autocompletion import autocomplete
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\cli\autocompletion.py", line 8, in <module>
    from pip._internal.cli.main_parser import create_main_parser
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\cli\main_parser.py", line 11, in <module>
    from pip._internal.commands import (
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\commands\__init__.py", line 6, in <module>
    from pip._internal.commands.completion import CompletionCommand
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\commands\completion.py", line 6, in <module>
    from pip._internal.cli.base_command import Command
  File "C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\cli\base_command.py", line 26, in <module>
    from pip._internal.index import PackageFinder
ImportError: cannot import name 'PackageFinder' from 'pip._internal.index' (C:\Users\User\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip\_internal\index\__init__.py)

как установить pip? помогите, пожалуйста