def METHOD_NAME(cls, server_cert_path, client_cert_path, client_key_path):
    client_cert, client_key = None, None
    server_cert = cls._open_certificate(server_cert_path)
    if client_cert_path is not None:
        client_cert = cls._open_certificate(client_cert_path)
    if client_key_path is not None:
        client_key = cls._open_private_key(client_key_path)
    return server_cert, client_cert, client_key