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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def send_notification(self, user, sender=None, **kwargs):
 """ An intermediary function for sending an notification email informing a pre-existing, active user that they have been added to a new organization. """

        if not user.is_active:
            return False
        self.email_message(
            user, self.notification_subject, self.notification_body, sender, **kwargs
        ).send()
        return True