def send_body(self, f, protocol_version):
        if protocol_version > 1:
            raise UnsupportedOperation(
                "Credentials-based authentication is not supported with "
                "protocol version 2 or higher.  Use the SASL authentication "
                "mechanism instead.")
        write_short(f, len(self.creds))
        for credkey, credval in self.creds.items():
            write_string(f, credkey)
            write_string(f, credval)
dataset/ETHPy150Open datastax/python-driver/cassandra/protocol.py/CredentialsMessage.send_body/original