安装pyqt5时报错Preparing metadata (pyproject.toml) ... error

解决方案尝试
先安装​​pyqt5​​依赖项：

1、更新python3.7

sudo add-apt-repository ppa:deadsnakes/ppa
sudo apt-get update
sudo apt-get upgrade
sudo apt-get autoremove
sudo apt-get install python3.7
sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.7 2
sudo update-alternatives --config python3
sudo apt-get install python3.7-dev
sudo apt-get install libhdf5-dev

2、更新pip3：

sudo python3 -m pip install --upgrade pip

3、安装pyqt5的依赖项

sudo apt install pyqt5*

sudo apt install qt5-default qttools5-dev-tools

4、最后再安装pyqt5

sudo pip3 install pyqt5
sudo pip3 install pyqt5-tools