def __create_action(self, main_root):
		action_dir = os.path.join(main_root, 'action')
		safe_mkdir(action_dir)

		actions = set()
		for unit, param in self.__task.data['workflow'].items():
			actions.add(param['type'])
		self.__action_mgr.create_actions(actions, action_dir)
def chart_title(self):
        """Returns a title for the chart."""
        if self.field:
            return 'Top filtered results for "{0:s}"'.format(self.field)
        return 'Top results for an unknown field after filtering'