1、在线下载安装
pip3 install PyQ5
2、离线包安装--首先先下载安装包
PyQt5-5.8.2-5.8.0-cp35.cp36.cp37-none-win_amd64.whl
pip3 install C:\Users\guoxunqiang\Desktop\pyqtsee5\PyQt5-5.8.2-5.8.0-cp35.cp36.cp37-none-win_amd64.whl
3、安装PyQT5--tools
pip3 install PyQT5-tools或离线包安装https://pypi.org/project/pyqt5tools/#files