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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 sql_flush(self, style, tables, sequences, allow_cascade=False):
 """ Truncate all existing tables in current keyspace. :returns: an empty list """


        for table in tables:
            qs = "TRUNCATE {}".format(table)
            self.connection.connection.execute(qs)

        return []