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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 invalidate_metadata(self, name=None, database=None):
 """ Issue INVALIDATE METADATA command, optionally only applying to a particular table. See Impala documentation. Parameters name : string, optional Table name. Can be fully qualified (with database) database : string, optional """

        stmt = 'INVALIDATE METADATA'
        if name is not None:
            stmt = self._table_command(stmt, name, database=database)
        self._execute(stmt)