Fixed use of LightningCLI in computer_vision_fine_tuning.py example (Lightning-AI#9934)

Author: mauvilsa

CHANGELOG.md

@@ -544,6 +544,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Reset `val_dataloader` in `tuner/batch_size_scaling` ([#9857](https://github.com/PyTorchLightning/pytorch-lightning/pull/9857))
 
 
+- Fixed use of `LightningCLI` in computer_vision_fine_tuning.py example ([#9934](https://github.com/PyTorchLightning/pytorch-lightning/pull/9934))
+
+
 ## [1.4.9] - 2021-09-30
 
 - Fixed `lr_find` to generate same results on multiple calls ([#9704](https://github.com/PyTorchLightning/pytorch-lightning/pull/9704))

pl_examples/domain_templates/computer_vision_fine_tuning.py

@@ -34,6 +34,9 @@
 
 Note:
     See: https://pytorch.org/tutorials/beginner/transfer_learning_tutorial.html
+
+To run:
+    python computer_vision_fine_tuning.py fit
 """
 
 import logging
@@ -265,7 +268,7 @@ def configure_optimizers(self):
 
 class MyLightningCLI(LightningCLI):
     def add_arguments_to_parser(self, parser):
-        parser.add_class_arguments(MilestonesFinetuning, "finetuning")
+        parser.add_lightning_class_args(MilestonesFinetuning, "finetuning")
         parser.link_arguments("data.batch_size", "model.batch_size")
         parser.link_arguments("finetuning.milestones", "model.milestones")
         parser.link_arguments("finetuning.train_bn", "model.train_bn")
@@ -277,11 +280,6 @@ def add_arguments_to_parser(self, parser):
             }
         )
 
-    def instantiate_trainer(self, *args):
-        finetuning_callback = MilestonesFinetuning(**self._get(self.config_init, "finetuning"))
-        self.trainer_defaults["callbacks"] = [finetuning_callback]
-        return super().instantiate_trainer(*args)
-
 
 def cli_main():
     MyLightningCLI(TransferLearningModel, CatDogImageDataModule, seed_everything_default=1234)