'Like :meth:`send_catch_log` but supports returning `deferreds`_ from
signal handlers.
Returns a Deferred that gets fired once all signal handlers
deferreds were fired. Send a signal, catch exceptions and log them.
The keyword arguments are passed to the signal handlers (connected
through the :meth:`connect` method).
.. _deferreds: http://twistedmatrix.com/documents/current/core/howto/defer.html'

def send_catch_log_deferred(self, signal, **kwargs):

    kwargs.setdefault('sender', self.sender)
    return _signal.send_catch_log_deferred(signal, **kwargs)
