bip39 VS python-mnemonic

Download the offline version of the BIP39 tool via https://github.com/iancoleman/bip39/releases/latest. Right click on bip39-standalone.html and save the file.

You could make this with a Raspberry Pi Zero and the stand-alone version of the Coleman Web page+javascript https://github.com/iancoleman/bip39/releases/latest/

Since what I just said may be confusing... here it is in practice with a link so you can try it for yourself using Ian Coleman's Mnemonic Code Converter:

With Christmas coming around and the bull market upon us, I thought it would be a good time to remind everyone one about the art of mnemonic memorization. The idea is you take a BIP39 seed, then make a poem, story, limerick, or song using the words to help you remember. If you gift bitcoin, you can include the writing with the seed-card you provide to help the recipient remember as well. If you want to play along, go to Ian's BIP39 page and generate a valid seed mnemonic then see if you can't create a blurb of text that includes all the words.

You can try Ian Coleman's tool at : https://iancoleman.io/bip39/

13) Go to https://iancoleman.io/bip39/. There you need to change "Coin" value of the dropdown to "ETH – Ethereum". After that you can paste Secret phrase associated with Key 1 to “BIP39 Mnemonic” section

As I learned how to build websites, I wanted to use my new skill to help the crypto community in any way I can. So, I made a wallet generator website. It's like iancoleman BIP39, but with a nicer and more user-friendly design inspired by Tornado Cash, a simple way to make wallets from files/images, and support for Monero!

I looked on https://iancoleman.io/bip39/ but didn't see how I might get something useful there.

Yes. BIP39 defines a check word to ensure the previous words are correct. You can read the spec here: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

ColdCard follows the BIP-39 standard for encoding the wallet's seed as a series of 24 words (a.k.a. "seed menmonic", sometimes called a recovery phrase). If you followed the instructions you were given when initializing it and you've stored your seed mnemonic safely in the real world (not digitally where it can be more easily discovered), you're fine. In the event you lose or damage your ColdCard, you can initialize a new wallet--ANY wallet that follows the BIP-39 standard, which is pretty universal these days--and the wallet will regenerate the same private keysthat your original ColdCard did, in the same order.

... and BIP-39

Look-up "BIP32", "BIP39" and "BIP44", those will point you to documents describing precisely how seed phrases are converted into crypto keys.

i think bip39 is what you want to look up.

Not correct See this: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki