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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 truncate_table(self, table_name, database=None):
 """ Delete all rows from, but do not drop, an existing table Parameters table_name : string database : string, default None (optional) """

        statement = ddl.TruncateTable(table_name, database=database)
        self._execute(statement, False)