How to resume training

I don’t understand how to resume the training (from the last checkpoint).
The following:
trainer = pl.Trainer(gpus=1, default_root_dir=save_dir)
saves but does not resume from the last checkpoint.
The following code starts the training from scratch (but I read that it should resume):

logger = TestTubeLogger(save_dir=save_dir, name="default", version=0)
trainer = pl.Trainer(gpus=1, default_root_dir=save_dir, logger = logger)

this is not what I wanted, I would like an automatic resume from the last checkpoint

I don’t think that’s possible since a new Trainer instance won’t have any info regarding the checkpoint state saved in the previous training.

ok thank you very much!