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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 is_archive(self):
 """ Given a parsed feed, returns True if this is an archive feed """


        ns_prefix = self.archive_namespace
        if ns_prefix:
            if ns_prefix + '_archive' in self.feed.feed:
                # This is declared to be an archive view
                return True
            if ns_prefix + '_current' in self.feed.feed:
                # This is declared to be the current view
                return False

        # Either we don't have the namespace, or the view wasn't declared.
        rels = collections.defaultdict(list)
        for link in self.feed.feed.links:
            rels[link.rel].append(link.href)

        return ('current' in rels and
                ('self' not in rels or
                 rels['self'] != rels['current']))