不知为何pycharm python库又不能正常安装了_no matching distribution found for pyqt

Collecting pyqt5-stubs

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  Could not find a version that satisfies the requirement pyqt5-stubs (from versions: )
No matching distribution found for pyqt5-stubs
You are using pip version 9.0.1, however version 19.1.1 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' command.

后来翻译了一下：

收集pyqt5-stubs

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   找不到满足pyqt5-stubs要求的版本（来自版本:)
找不到pyqt5-stubs的匹配分布
您正在使用pip版本9.0.1，但版本19.1.1可用。
您应该考虑通过'python -m pip install --upgrade pip'命令进行升级。

是pip版本的问题：

于是我升级了一下pip

后来发现版本太高不能使用

于是又降级

另外一种方式，降级pip的版本

python -m pip install --upgrade pip==9.0.3

发现有降回去了，不能用了

后来自己乱编了一个版本

python -m pip install --upgrade pip==10.0.0

发现有的东西适合 高版本的，有的适合低版本的pip