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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 _collection_length(self, final_set):
 """ Return the length of the final collection, directly asking redis for the count without calling sort """

        conn = self.cls.get_connection()

        # we have a sorted set without need to sort, use zcard
        if self._has_sortedsets:
            return conn.zcard(final_set)

        # we have a stored collection, without other filter, use llen
        elif self.stored_key and not self._lazy_collection['sets']\
                and len(self._lazy_collection['intersects']) == 1:

            return conn.llen(final_set)

        # normal call
        return super(ExtendedCollectionManager, self)._collection_length(final_set)