def METHOD_NAME(self):
    logger.info(f"testing private key at {PRIVATE_KEY}…")
    if (
        not PRIVATE_KEY.exists()
        or not PRIVATE_KEY.is_file()
        or not os.access(PRIVATE_KEY, os.R_OK)
    ):
        logger.critical("\tprivate key is not a readable path")
        sys.exit(1)
    try:
        self.fingerprint = binascii.hexlify(
            paramiko.RSAKey.from_private_key(
                open(PRIVATE_KEY, "r")
            ).get_fingerprint()
        ).decode("ASCII")
    except Exception as exc:
        logger.critical("\tprivate key is not valid RSA")
        logger.exception(exc)
        sys.exit(1)
    else:
        logger.info(f"\tprivate key is available and readable ({self.fingerprint})")