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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 system_commands(self, action):
 """ Perform system commands """

        if action == 'backup':
            status = self.api_action.backup()
            if status[0]:
                notify_confirm('Vent backup successful')
            else:
                notify_confirm('Vent backup could not be completed')
        elif action == 'start':
            status = self.api_action.start()
            if status[0]:
                notify_confirm('System start complete. '
                               'Press OK.')
            else:
                notify_confirm(status[1])
        elif action == 'stop':
            status = self.api_action.stop()
            if status[0]:
                notify_confirm('System stop complete. '
                               'Press OK.')
            else:
                notify_confirm(status[1])
        elif action == 'configure':
            # TODO
            form_args = {'name': 'Change vent configuration',
                         'get_configure': self.api_action.get_configure,
                         'save_configure': self.api_action.save_configure,
                         'restart_tools': self.api_action.restart_tools,
                         'vent_cfg': True}
            add_kargs = {'form': EditorForm,
                         'form_name': 'CONFIGUREVENT',
                         'form_args': form_args}
            self.add_form(**add_kargs)
        elif action == 'reset':
            okay = npyscreen.notify_ok_cancel(
                "This factory reset will remove ALL of Vent's user data, "
                'containers, and images. Are you sure?',
                title='Confirm system command')
            if okay:
                status = self.api_action.reset()
                if status[0]:
                    notify_confirm('Vent reset complete. '
                                   'Press OK to exit Vent Manager console.')
                else:
                    notify_confirm(status[1])
                MainForm.exit()
        elif action == 'gpu':
            gpu = Gpu(pull=True)
            if gpu[0]:
                notify_confirm('GPU detection successful. '
                               'Found: ' + gpu[1])
            else:
                if gpu[1] == 'Unknown':
                    notify_confirm('Unable to detect GPUs, try `make gpu` '
                                   'from the vent repository directory. '
                                   'Error: ' + str(gpu[2]))
                else:
                    notify_confirm('No GPUs detected.')
        elif action == 'restore':
            backup_dir_home = os.path.expanduser('~')
            backup_dirs = [f for f in os.listdir(backup_dir_home) if
                           f.startswith('.vent-backup')]
            form_args = {'restore': self.api_action.restore,
                         'dirs': backup_dirs,
                         'name': 'Pick a version to restore from' + '\t'*8 +
                                 '^T to toggle main',
                         'color': 'CONTROL'}
            add_kargs = {'form': BackupForm,
                         'form_name': 'CHOOSEBACKUP',
                         'form_args': form_args}
            self.add_form(**add_kargs)
        return