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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_object(self, request, year, month, day, slug):
 """ Retrieve the discussions by entry's slug. """

        return get_object_or_404(Entry, slug=slug,
                                 publication_date__year=year,
                                 publication_date__month=month,
                                 publication_date__day=day)