docs: def dump(self, sender=None, **kwargs):
          '''Retrieve raw email dump for this bounce.
  
          :param sender: A :class:`BounceDump` object to get dump with.
              Defaults to `None`.
          :param \*\*kwargs: Keyword arguments passed to
              :func:`requests.request`.
          '''
          if sender is None:
              if self._sender is None:
                  sender = _default_bounce_dump
              else:
                  sender = BounceDump(api_key=self._sender.api_key,
                                      test=self._sender.test,
                                      secure=self._sender.secure)
          return sender.get(self.id, **kwargs)