<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def unwrap(self, wrapping_key, wrapped_key):
 # type: (bytes, bytes) -> bytes """Unwrap key using AES keywrap. :param bytes wrapping_key: Loaded key with which to unwrap :param bytes wrapped_key: Wrapped key to unwrap :returns: Unwrapped key :rtype: bytes """

        if self.java_name not in ("AES", "AESWrap"):
            raise NotImplementedError('"unwrap" is not supported by this cipher')

        try:
            return keywrap.aes_key_unwrap(wrapping_key=wrapping_key, wrapped_key=wrapped_key, backend=default_backend())
        except Exception:
            error_message = "Key unwrap failed"
            _LOGGER.exception(error_message)
            raise UnwrappingError(error_message)