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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 get_last_live_chat(self):
 """ Check if there is a live chat that ended in the last 3 days, and return it. We will display a link to it on the articles page. """

        now = datetime.now()

        lcqs = self.get_query_set()
        lcqs = lcqs.filter(
            chat_ends_at__lte=now,
            ).order_by('-chat_ends_at')
        for itm in lcqs:
            if itm.chat_ends_at + timedelta(days=3) > now:
                return itm
        return None