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def find_stealth_address(scan_pubkey, spend_pubkeys, ephemkey, multisig_m = 0):
##### This takes scan_pubkey and spend_pubkeys and creates the new address
    S1 = diffie_hellman(ephemkey.secret, scan_pubkey)
    ##### Scan pubkey * ephem_secret (this function is for generating the address for sending.)
    c = sha256(S1)
    ##### Hashing the compressed pubkey shared secret once with sha256 to get an integer.
    shared_point = EC_KEY(c).pubkey.point
    ##### Generate the point from the shared secret and get the point (pubkey point)
    addr_pubkey = []
    ##### initialize address pubkey list
    if len(spend_pubkeys) == 1:
    ##### If Length of spend pubkeys (should be same as N, its sanity is checked in separate function.)
        point = ser_to_point(spend_pubkeys[0]) + shared_point
        ##### Add the spend pubkey point to the shared point
        addr_pubkey.append(point_to_ser(point))
        ##### Add compressed pubkey to addr pubkey list
        address = public_key_to_bc_address(addr_pubkey[0])
        ##### Get address
    else:
    ##### When N > 1
        assert multisig_m > 0 and multisig_m <= len(spend_pubkeys)
        ##### sanity check, M should be at least 1, M should be less or equal to N.
        for i in range(len(spend_pubkeys)):
            point = ser_to_point(spend_pubkeys[i]) + shared_point
            ##### Add each of N spend pubkeys to the same shared secret point
            addr_pubkey.append(point_to_ser(point).encode('hex'))
            ##### Add the pubkeys to the addr pubkeys list
        from transaction import Transaction
        redeem_script = Transaction.multisig_script(sorted(addr_pubkey), multisig_m)
        ##### Generate redeemscript by sorting the addr_pubkeys first (canonical)
        address = hash_160_to_bc_address(hash_160(redeem_script.decode('hex')), 5)
        ##### Generate the p2sh address
    return address