f data to decrypt.
  received_mac_tag : bytes/bytearray/memoryview
    This is the *binary* MAC, as received from the sender.
:Keywords:
  output : bytearray/memoryview
    The location where the plaintext must be written to.
    If ``None``, the plaintext is returned.
:Return: the plaintext as ``bytes`` or ``None`` when the ``output``
    parameter specified a location for the result.
:Raises ValueError:
    if the MAC does not match. The message has been tampered with
    or the key is incorrect.
rt