def METHOD_NAME(self, request, activation_key):
    """
    Given an an activation key, look up and activate the user
    account corresponding to that key (if possible).
    After successful activation, the signal
    ``registration.signals.user_activated`` will be sent, with the
    newly activated ``User`` as the keyword argument ``user`` and
    the class of this backend as the sender.
    """
    activated = RegistrationProfile.objects.activate_user(activation_key)
    if activated:
        signals.user_activated.send(sender=self.__class__,
                                    user=activated,
                                    request=request)
    return activated