How to use the dotbot.dispatcher.DispatchError function in dotbot

exit(1)
        tasks = read_config(options.config_file)
        if not isinstance(tasks, list):
            raise ReadingError('Configuration file must be a list of tasks')
        if options.base_directory:
            base_directory = options.base_directory
        else:
            # default to directory of config file
            base_directory = os.path.dirname(os.path.realpath(options.config_file))
        os.chdir(base_directory)
        dispatcher = Dispatcher(base_directory)
        success = dispatcher.dispatch(tasks)
        if success:
            log.info('\n==> All tasks executed successfully')
        else:
            raise DispatchError('\n==> Some tasks were not executed successfully')
    except (ReadingError, DispatchError) as e:
        log.error('%s' % e)
        exit(1)
    except KeyboardInterrupt:
        log.error('\n==> Operation aborted')
        exit(1)

def _setup_context(self, base_directory):
        path = os.path.abspath(os.path.realpath(
            os.path.expanduser(base_directory)))
        if not os.path.exists(path):
            raise DispatchError('Nonexistent base directory')
        self._context = Context(path)