This tool lets you generate extended private keys and extended public keys in various formats for use with Electrum. It also lets you derive xpubs and child xprvs from parent xprvs. It's designed so that you can pipe the output to electrum and directly create wallets with it. Run it with python3 xprv.py -h to see the options.

It requires electrum 4.3.1 or later installed on your system. It uses electrum functions to do it's job.