def _init_steps(self,):
        self._check_old_yaml_format()
        config_steps = self.flow_config.steps
        self._check_infinite_flows(config_steps)
        steps = []
        for number, step_config in config_steps.items():
            specs = self._visit_step(number, step_config)
            steps.extend(specs)
        return sorted(steps, key=attrgetter("step_num"))