Transform an old copay Spanish mnemonic (with the composed unicode bug) into a seed

old-copay-spanish-mnemonic-to-seed.py

import sys
import hashlib
import unicodedata


if len(sys.argv) != 2:
    print('Usage: python3 old-copay-spanish-mnemonic-to-seed.py "here go the mnemonic words"')
    exit(1)

mnemonic = sys.argv[1]
composed = unicodedata.normalize('NFKC', mnemonic).encode('utf-8')
passphrase = 'mnemonic'.encode('utf-8')
stretched = hashlib.pbkdf2_hmac('sha512', composed, passphrase, 2048)
seed = stretched[:64]
print('seed: ' + seed.hex())

Run with:

python3 old-copay-spanish-mnemonic-to-seed.py "here go the mnemonic words"