How to use the duniterpy.key.SigningKey.from_credentials function in duniterpy

def test_save_and_load_from_private_key_file(self):
        sign_key_save = SigningKey.from_credentials("alice", "password", ScryptParams())
        sign_key_save.save_private_key(TEST_FILE_PATH)

        sign_key_load = SigningKey.from_private_key(TEST_FILE_PATH)
        self.assertEqual(sign_key_save.sk, sign_key_load.sk)

def test_from_credentials(self):
        sign_key = SigningKey.from_credentials("alice", "password", ScryptParams())
        verify_key = VerifyingKey(sign_key.pubkey)
        self.assertEqual(verify_key.vk, sign_key.vk)

"""
    # Create Client from endpoint string in Duniter format
    client = Client(BMAS_ENDPOINT)

    # Get the node summary infos to test the connection
    response = await client(bma.node.summary)
    print(response)

    # prompt hidden user entry
    salt = getpass.getpass("Enter your passphrase (salt): ")

    # prompt hidden user entry
    password = getpass.getpass("Enter your password: ")

    # create key from credentials
    key = SigningKey.from_credentials(salt, password)
    pubkey_from = key.pubkey

    # prompt entry
    pubkey_to = input("Enter certified pubkey: ")

    # capture current block to get version and currency and blockstamp
    current_block = await client(bma.blockchain.current)

    # create our Identity document to sign the Certification document
    identity = await get_identity_document(client, current_block, pubkey_to)
    if identity is None:
        print("Identity not found for pubkey {0}".format(pubkey_to))
        # Close client aiohttp session
        await client.close()
        sys.exit(1)

# you'll have to use one of your private keys instead
PRIVATE_KEYS_FILE_PATH = os.path.join(home_path, ".duniter_account_private_keys.txt")

################################################

# prompt hidden user entry
salt = getpass.getpass("Enter your passphrase (salt): ")

# prompt hidden user entry
password = getpass.getpass("Enter your password: ")

# prompt public key
pubkey = input("Enter your public key: ")

# init signer instance
signer = SigningKey.from_credentials(salt, password)

# check public key
if signer.pubkey != pubkey:
    print("Bad credentials!")
    sys.exit(1)

# save private keys in a file (json format)
signer.save_private_key(PRIVATE_KEYS_FILE_PATH)

# document saved
print("Private keys for public key %s saved in %s" % (pubkey, PRIVATE_KEYS_FILE_PATH))

# load private keys from file
loaded_signer = SigningKey.from_private_key(PRIVATE_KEYS_FILE_PATH)  # type: SigningKey

# check public key from file

# you'll have to use one of your private keys instead
PRIVATE_KEY_FILE_PATH = os.path.join(home_path, ".duniter_account_wif_v1.duniterkey")

################################################

# prompt hidden user entry
salt = getpass.getpass("Enter your passphrase (salt): ")

# prompt hidden user entry
password = getpass.getpass("Enter your password: ")

# prompt public key
pubkey = input("Enter your public key: ")

# init signer instance
signer = SigningKey.from_credentials(salt, password)

# check public key
if signer.pubkey != pubkey:
    print("Bad credentials!")
    sys.exit(1)

# save private key in a file (WIF v1 format)
signer.save_wif_file(PRIVATE_KEY_FILE_PATH)

# document saved
print(
    "Private key for public key %s saved in %s" % (signer.pubkey, PRIVATE_KEY_FILE_PATH)
)

try:
    # load private keys from file

# CONFIG #######################################

CLEARTEXT_AA_MESSAGE_PATH = "/tmp/duniter_cleartext_aa_message.txt"

################################################

if __name__ == "__main__":
    # prompt hidden user entry
    salt = getpass.getpass("Enter your passphrase (salt): ")

    # prompt hidden user entry
    password = getpass.getpass("Enter your password: ")

    # init SigningKey instance
    signing_key = SigningKey.from_credentials(salt, password)

    # Enter the multi-line message (stop with Ctrl-D below last line to end)
    print("Enter your message (Ctrl-D below last line to end):")
    message = sys.stdin.read()

    print("Message signed by puplic key : {pubkey}".format(pubkey=signing_key.pubkey))

    comment = "generated by Duniterpy {0}".format(__version__)
    # Dash escape the message and sign it
    aa_cleartext_message = AsciiArmor.create(
        message, None, [signing_key], None, signatures_comment=comment
    )

    # Save cleartext ascii armor message in a file
    with open(CLEARTEXT_AA_MESSAGE_PATH, "w") as file_handler:
        file_handler.write(aa_cleartext_message)

def get_signed_raw_revocation_document(
    identity: Identity, salt: str, password: str
) -> str:
    """
    Generate account revocation document for given identity

    :param identity: Self Certification of the identity
    :param salt: Salt
    :param password: Password

    :rtype: str
    """
    revocation = Revocation(PROTOCOL_VERSION, identity.currency, identity, "")

    key = SigningKey.from_credentials(salt, password)
    revocation.sign([key])
    return revocation.signed_raw()