from pybitcointools.deterministic import raw_crack_bip32_privkey, bip32_deserialize, bip32_serialize, bip32_privtopub
from pybitcointools.main import decode_privkey, encode_privkey

parent_pub = 'xpub661MyMwAqRbcEnKbXcCqD2GT1di5zQxVqoHPAgHNe8dv5JP8gWmDproS6kFHJnLZd23tWevhdn4urGJ6b264DfTGKr8zjmYDjyDTi9U7iyT'
wif_key = encode_privkey(decode_privkey('KyqcQVzcp7cHEMEDHQaz5eaE5azsRHaE4ukkeqwM2vdiQwBYtxeb'), 'bin_compressed')
for i in xrange(2**31 -1):
    priv = (b'x04x88xADxE4', 1, 0, i, b'', wif_key)
    pkey =  raw_crack_bip32_privkey(bip32_deserialize(parent_pub), priv)
    final_key = bip32_serialize(pkey)
    if bip32_privtopub(final_key) == parent_pub:
        print final_key
        break