def command_umount(self, system_id, *system_ids):
system_ids = (system_id,) + system_ids<EOL>has_failed = False<EOL>for system_id in system_ids:<EOL><INDENT>try:<EOL><INDENT>system = SystemModel.create_by_id(system_id, self.environment)<EOL>controller = SystemControllerModel(system, self.environment)<EOL>controller.unmount()<EOL><DEDENT>except SftpConfigException as e:<EOL><INDENT>sys.stderr.write('<STR_LIT>' % (system_id, str(e)))<EOL>has_failed = True<EOL><DEDENT><DEDENT>if has_failed:<EOL><INDENT>sys.exit(<NUM_LIT:1>)<EOL><DEDENT>
Unmounts the specified sftp system.
        Usage: sftpman umount {id}..