解决方法:
python -m ensurepip
Looking in links: c:\Users\admin\AppData\Local\Temp\tmp5wtkuosb
Requirement already satisfied: setuptools in d:\app\pycharm\pycharm edu 2020.2.3\python\lib\site-packages (49.2.1)
Processing c:\users\admin\appdata\local\temp\tmp5wtkuosb\pip-20.2.3-py2.py3-none-any.whl
Installing collected packages: pip
Successfully installed pip-20.2.3
python -m pip install --upgrade pip