我在这里遇到了同样的问题，我尝试了所有方法，但最终我找到了解决方法:

I had same issue here, and i tried everything, but finally i found the solution :

我不得不将点数从19版降级到18.1:

I had to downgrade pip from version 19 to 18.1 :

pip install pip==18.1

然后安装PyInstaller:

Then install PyInstaller :

pip install pyinstaller

.

如您所见，我设法安装了它:

As you see i managed to install it : .

之后，您可以再次升级点数:

After that you can upgrade your pip again :

python -m pip install --upgrade pip