from remote
authorities so this both won't be available for newly started relays and
may be up to around an hour out of date.

.. versionchanged:: 1.3.0
   Changed so we'd fetch our own descriptor if no 'relay' is provided.

:param str relay: fingerprint or nickname of the relay to be queried
:param object default: response if the query fails

:returns: :class:`~stem.descriptor.router_status_entry.RouterStatusEntryV3`
  for the given relay

:raises:
  * :class:`stem.DescriptorUnavailable` if unable to provide a descriptor
    for the given relay
  * :class:`stem.ControllerError` if unable to query the descriptor
  * **ValueError** if **relay** doesn't conform with the pattern for being
    a fingerprint or nickname

  An exception is only raised if we weren't provided a default response.
NrN