使用pip命令出现错误：
pip install jupyter
Fatal error in launcher: Unable to create process using '"D:\Python\Python38-64.0\python.exe" "A:\Python\Python38-64.0\Scripts\pip.exe" install jupyter': ???????????
在检查环境变量后未果。在终端输入该命令成功：
python -m pip install --upgrade --force-reinstall pip
