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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 cleanup_full_hashes(self, keep_expired_for=(60 * 60 * 12)):
 """Remove long expired full_hash entries."""

        q = '''DELETE FROM full_hash WHERE expires_at < datetime(current_timestamp, '-{} SECONDS')
        '''
        log.info('Cleaning up full_hash entries expired more than {} seconds ago.'.format(keep_expired_for))
        with self.get_cursor() as dbc:
            dbc.execute(q.format(int(keep_expired_for)))