Update trainer

paddlehub/finetune/trainer.py

@@ -32,7 +32,7 @@ class Trainer(object):
 
     Args:
         model(paddle.nn.Layer) : Model to train or evaluate.
-        strategy(paddle.optimizer.Optimizer) : Optimizer strategy.
+        optimizer(paddle.optimizer.Optimizer) : Optimizer for loss.
         use_vdl(bool) : Whether to use visualdl to record training data.
         checkpoint_dir(str) : Directory where the checkpoint is saved, and the trainer will restore the
             state and model parameters from the checkpoint.
@@ -51,16 +51,19 @@ class Trainer(object):
 
     def __init__(self,
                  model: paddle.nn.Layer,
-                 strategy: paddle.optimizer.Optimizer,
+                 optimizer: paddle.optimizer.Optimizer,
                  use_vdl: bool = True,
                  checkpoint_dir: str = None,
                  compare_metrics: Callable = None):
         self.nranks = paddle.distributed.get_world_size()
         self.local_rank = paddle.distributed.get_rank()
         self.model = model
-        self.optimizer = strategy
+        self.optimizer = optimizer
         self.checkpoint_dir = checkpoint_dir if checkpoint_dir else 'ckpt_{}'.format(time.time())
 
+        if not isinstance(self.model, paddle.nn.Layer):
+            raise TypeError('The model {} is not a `paddle.nn.Layer` object.'.format(self.model.__name__))
+
         if self.local_rank == 0 and not os.path.exists(self.checkpoint_dir):
             os.makedirs(self.checkpoint_dir)