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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 schedule_jabber_message(message, to, sender=None, priority=None):
 """Schedules Jabber XMPP message for delivery. :param str message: text to send. :param list|str|unicode to: recipients addresses or Django User model heir instances with `email` attributes. :param User sender: User model heir instance :param int priority: number describing message priority. If set overrides priority provided with message type. """

    schedule_messages(message, recipients('xmppsleek', to), sender=sender, priority=priority)