Bip39 buffer is not defined https://blogfreely.net/travenmdoq/create-your-own-distinct-bip39-mnemonic-expression-with-python-scripts While it utilizes BIP32 approach you may however import BIP39 seeds into Electrum wallet. Also besides BIp32 You can find BIP44 Edition which some wallet use for your technology of seeds. BIP39 is like the ability to “read” and comprehend the seed phrase... https://dirstop.com/story25461224/bip39-seed-phrase-generator-5-tips-about-bip39-checksum-you-can-use-today-https-linktr-ee-bip39