revise load parameters

deepspeech/models/deepspeech2.py

@@ -21,8 +21,8 @@ from yacs.config import CfgNode
 from deepspeech.modules.conv import ConvStack
 from deepspeech.modules.ctc import CTCDecoder
 from deepspeech.modules.rnn import RNNStack
-from deepspeech.utils import checkpoint
 from deepspeech.utils import layer_tools
+from deepspeech.utils.checkpoint import Checkpoint
 from deepspeech.utils.log import Log
 
 logger = Log(__name__).getlog()
@@ -222,7 +222,7 @@ class DeepSpeech2Model(nn.Layer):
                     rnn_size=config.model.rnn_layer_size,
                     use_gru=config.model.use_gru,
                     share_rnn_weights=config.model.share_rnn_weights)
-        infos = checkpoint.load_parameters(
+        infos = Checkpoint().load_parameters(
             model, checkpoint_path=checkpoint_path)
         logger.info(f"checkpoint info: {infos}")
         layer_tools.summary(model)