Trainstage1 parent dir was not created

[mo230761]

when I run TrainStage1_7b.sh，because you modified the _save method of the trainer, it will not create a parent directory for checkpoints like checkpoint-10 (where the number represents the save steps). This will cause subsequent parameter files to not be saved, leading to errors

[yuzhou914]

Thanks for your interest in our work. There might be some small code typos when we push on github, while you could simply fix them for further usage.

[mo230761]

Thanks!