AttributeError: 'NoneType' object has no attribute 'modules'

[talhaanwarch]

When i use 'freeze' strategy speech_recognition tutorial. i got following error

AttributeError                            Traceback (most recent call last)
/tmp/ipykernel_6283/3432455275.py in <module>
      1 # 3. Create the trainer and finetune the model
      2 trainer = flash.Trainer(max_epochs=1, gpus=torch.cuda.device_count())
----> 3 trainer.finetune(model, datamodule=datamodule, strategy="freeze")
      4 

~/venv/lib/python3.8/site-packages/flash/core/trainer.py in finetune(self, model, train_dataloader, val_dataloaders, datamodule, strategy)
    187         """
    188         self._resolve_callbacks(model, strategy)
--> 189         return super().fit(model, train_dataloader, val_dataloaders, datamodule)
    190 
    191     def _resolve_callbacks(self, model: LightningModule, strategy: Optional[Union[str, BaseFinetuning]] = None) -> None:

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/trainer.py in fit(self, model, train_dataloaders, val_dataloaders, datamodule, train_dataloader, ckpt_path)
    733             )
    734             train_dataloaders = train_dataloader
--> 735         self._call_and_handle_interrupt(
    736             self._fit_impl, model, train_dataloaders, val_dataloaders, datamodule, ckpt_path
    737         )

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/trainer.py in _call_and_handle_interrupt(self, trainer_fn, *args, **kwargs)
    680         """
    681         try:
--> 682             return trainer_fn(*args, **kwargs)
    683         # TODO: treat KeyboardInterrupt as BaseException (delete the code below) in v1.7
    684         except KeyboardInterrupt as exception:

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/trainer.py in _fit_impl(self, model, train_dataloaders, val_dataloaders, datamodule, ckpt_path)
    768         # TODO: ckpt_path only in v1.7
    769         ckpt_path = ckpt_path or self.resume_from_checkpoint
--> 770         self._run(model, ckpt_path=ckpt_path)
    771 
    772         assert self.state.stopped

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/trainer.py in _run(self, model, ckpt_path)
   1128         # SET UP TRAINING
   1129         # ----------------------------
-> 1130         self.call_hook("on_before_accelerator_backend_setup")
   1131         self.accelerator.setup_environment()
   1132         self._call_setup_hook()  # allow user to setup lightning_module in accelerator environment

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/trainer.py in call_hook(self, hook_name, pl_module, *args, **kwargs)
   1475             callback_fx = getattr(self, hook_name, None)
   1476             if callable(callback_fx):
-> 1477                 callback_fx(*args, **kwargs)
   1478 
   1479             # next call hook in lightningModule

~/venv/lib/python3.8/site-packages/pytorch_lightning/trainer/callback_hook.py in on_before_accelerator_backend_setup(self)
     36         """Called at the beginning of fit (train + validate), validate, test, or predict, or tune."""
     37         for callback in self.callbacks:
---> 38             callback.on_before_accelerator_backend_setup(self, self.lightning_module)
     39 
     40     def on_configure_sharded_model(self) -> None:

~/venv/lib/python3.8/site-packages/pytorch_lightning/callbacks/finetuning.py in on_before_accelerator_backend_setup(self, trainer, pl_module)
    243 
    244     def on_before_accelerator_backend_setup(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule"):
--> 245         self.freeze_before_training(pl_module)
    246 
    247     @staticmethod

~/venv/lib/python3.8/site-packages/flash/core/finetuning.py in freeze_before_training(self, pl_module)
     53 
     54     def freeze_before_training(self, pl_module: LightningModule) -> None:
---> 55         self.freeze_using_attr_names(pl_module, self.attr_names, train_bn=self.train_bn)
     56 
     57     def freeze_using_attr_names(self, pl_module, attr_names: List[str], train_bn: bool = True):

~/venv/lib/python3.8/site-packages/flash/core/finetuning.py in freeze_using_attr_names(self, pl_module, attr_names, train_bn)
     60             if not attr or not isinstance(attr, nn.Module):
     61                 MisconfigurationException(f"Your model must have a {attr} attribute")
---> 62             self.freeze(modules=attr, train_bn=train_bn)
     63 
     64     def finetune_function(self, pl_module: LightningModule, epoch: int, optimizer: Optimizer, opt_idx: int):

~/venv/lib/python3.8/site-packages/pytorch_lightning/callbacks/finetuning.py in freeze(modules, train_bn)
    176             None
    177         """
--> 178         modules = BaseFinetuning.flatten_modules(modules)
    179         for mod in modules:
    180             if isinstance(mod, _BatchNorm) and train_bn:

~/venv/lib/python3.8/site-packages/pytorch_lightning/callbacks/finetuning.py in flatten_modules(modules)
    125 
    126         else:
--> 127             _modules = modules.modules()
    128 
    129         # Capture all leaf modules as well as parent modules that have parameters directly themsleves

AttributeError: 'NoneType' object has no attribute 'modules'