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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 cache_infos(self, queryset):
 """ Cache the number of entries published and the last modification date under each tag. """

        self.cache = {}
        for item in queryset:
            # If the sitemap is too slow, don't hesitate to do this :
            #   self.cache[item.pk] = (item.count, None)
            self.cache[item.pk] = (
                item.count, TaggedItem.objects.get_by_model(
                    self.entries_qs, item)[0].last_update)