Installing Python library failed Warning Retrying Errno 3

Q What should I do when the warning "WARNING: Retrying... [Errno -3]" appears while installing a library on UNIHIKER?
A This indicates that UNIHIKER is not connected to the network. Please connect it to the network first. If the error persists after connecting to the network, try switching the Python source or changing the WiFi.
Q What should I do if the Python code cannot be stopped after running?
A You can use the Ctrl+\ in the terminal to forcefully kill the process, or long-press the Home button on UNIHIKER for over 5s to terminate all Python programs.