0.7.6 breaks model checkpoint
🐛 Bug
training crashes when model checkpoint is triggered
To Reproduce
Identical code works in 0.7.5, hparam types used are int, float, str, bool
hparams is generated via test tube and saved in the module as self.hparams
-- Process 0 terminated with the following error:
Traceback (most recent call last):
  File "/opt/conda/lib/python3.6/site-packages/torch/multiprocessing/spawn.py", line 19, in _wrap
    fn(i, *args)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/distrib_data_parallel.py", line 389, in ddp_train
    self.run_pretrain_routine(model)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/trainer.py", line 1015, in run_pretrain_routine
    self.train()
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/training_loop.py", line 347, in train
    self.run_training_epoch()
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/training_loop.py", line 452, in run_training_epoch
    self.call_checkpoint_callback()
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/training_loop.py", line 790, in call_checkpoint_callback
    self.checkpoint_callback.on_validation_end(self, self.get_model())
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/utilities/distributed.py", line 10, in wrapped_fn
    return fn(*args, **kwargs)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/callbacks/model_checkpoint.py", line 241, in on_validation_end
    self._do_check_save(filepath, current, epoch)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/callbacks/model_checkpoint.py", line 275, in _do_check_save
    self._save_model(filepath)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/callbacks/model_checkpoint.py", line 142, in _save_model
    self.save_function(filepath)
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/training_io.py", line 260, in save_checkpoint
    checkpoint = self.dump_checkpoint()
  File "/opt/conda/lib/python3.6/site-packages/pytorch_lightning/trainer/training_io.py", line 355, in dump_checkpoint
    f' not {checkpoint["hparams_type"]}'
ValueError: ('The acceptable hparams type is dict or argparse.Namespace,', ' not TTNamespace')