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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_subdomain_zonefile_hash(self, fqn, zonefile_hash, cur=None):
 """ Does this zone file hash belong to this subdomain? """

        sql = 'SELECT COUNT(zonefile_hash) FROM {} WHERE fully_qualified_subdomain = ? and zonefile_hash = ?;'.format(self.subdomain_table)
        args = (fqn,zonefile_hash)

        cursor = None
        if cur is None:
            cursor = self.conn.cursor()
        else:
            cursor = cur

        rows = db_query_execute(cursor, sql, args)
        
        count = None
        for row in rows:
            count = row['COUNT(zonefile_hash)']
            break

        return (count > 0)