Return a deferred that will fire after the request is finished.

        Returns:

            Deferred: a new deferred that will fire appropriately

def after(self):
        """
        Return a deferred that will fire after the request is finished.

        Returns:

            Deferred: a new deferred that will fire appropriately

        """

        d = Deferred()
        self._after_deferreds.append(d)
        return d.chain