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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_for(self, query_type, value):
 """ Create a query and run it for the given arg if it doesn't exist, and return the tweets for the query. """

        from yacms.twitter.models import Query
        lookup = {"type": query_type, "value": value}
        query, created = Query.objects.get_or_create(**lookup)
        if created:
            query.run()
        elif not query.interested:
            query.interested = True
            query.save()
        return query.tweets.all()