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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 put_on_top(self, request, queryset):
 """ Put the selected entries on top at the current date. """

        queryset.update(publication_date=timezone.now())
        self.ping_directories(request, queryset, messages=False)
        self.message_user(request, _(
            'The selected entries are now set at the current date.'))