fix example (#10964)

python/ray/util/sgd/torch/examples/raysgd_torch_signatures.py

@@ -8,7 +8,12 @@ in the documentation.
 # yapf: disable
 
 # __torch_operator_start__
+import torch
+import torch.nn as nn
+from torch.utils.data import DataLoader
+
 from ray.util.sgd.torch import TrainingOperator
+from ray.util.sgd.torch.examples.train_example import LinearDataset
 
 class MyTrainingOperator(TrainingOperator):
     def setup(self, config):
@@ -44,10 +49,29 @@ class MyTrainingOperator(TrainingOperator):
         self.model, self.optimizer, self.criterion, self.scheduler = \
             self.register(models=model, optimizers=optimizer,
                           criterion=criterion,
-                          scheduler=scheduler)
+                          schedulers=scheduler)
         self.register_data(train_loader=train_loader, validation_loader=val_loader)
 # __torch_operator_end__
 
+# __torch_ray_start__
+import ray
+
+ray.init()
+# or ray.init(address="auto") to connect to a running cluster.
+# __torch_ray_end__
+
+# __torch_trainer_start__
+from ray.util.sgd import TorchTrainer
+
+trainer = TorchTrainer(
+    training_operator_cls=MyTrainingOperator,
+    scheduler_step_freq="epoch",  # if scheduler is used
+    config={"lr": 0.001, "batch_size": 64})
+
+# __torch_trainer_end__
+
+trainer.shutdown()
+
 # __torch_model_start__
 import torch.nn as nn
 
@@ -144,13 +168,6 @@ def scheduler_creator(optimizer, config):
 
 # __torch_scheduler_end__
 
-# __torch_ray_start__
-import ray
-
-ray.init()
-# or ray.init(address="auto") to connect to a running cluster.
-# __torch_ray_end__
-
 # __backwards_compat_start__
 from ray.util.sgd import TorchTrainer
 
@@ -167,15 +184,3 @@ trainer = TorchTrainer(
 # __backwards_compat_end__
 
 trainer.shutdown()
-
-# __torch_trainer_start__
-from ray.util.sgd import TorchTrainer
-
-trainer = TorchTrainer(
-    training_operator_cls=MyTrainingOperator,
-    scheduler_step_freq="epoch",  # if scheduler is used
-    config={"lr": 0.001, "batch_size": 64})
-
-# __torch_trainer_end__
-
-trainer.shutdown()