add train and eval script for LSTM

example/lstm_aclImdb/README.md

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+# LSTM Example
+
+## Description
+
+This example is for LSTM model training and evaluation.
+
+## Requirements
+
+- Install [MindSpore](https://www.mindspore.cn/install/en).
+
+- Download the dataset aclImdb_v1.
+
+> Unzip the aclImdb_v1 dataset to any path you want and the folder structure should be as follows:
+> ```
+> .
+> ├── train  # train dataset
+> └── test   # infer dataset
+> ```
+
+- Download the GloVe file.
+
+> Unzip the glove.6B.zip to any path you want and the folder structure should be as follows:
+> ```
+> .
+> ├── glove.6B.100d.txt
+> ├── glove.6B.200d.txt
+> ├── glove.6B.300d.txt    # we will use this one later.
+> └── glove.6B.50d.txt
+> ```
+
+> Adding a new line at the beginning of the file which named `glove.6B.300d.txt`. 
+> It means reading a total of 400,000 words, each represented by a 300-latitude word vector.
+> ```
+> 400000    300
+> ```
+
+## Running the Example
+
+### Training
+
+```
+python train.py --preprocess=true --aclimdb_path=your_imdb_path --glove_path=your_glove_path  > out.train.log 2>&1 & 
+```
+The python command above will run in the background, you can view the results through the file `out.train.log`.
+
+After training, you'll get some checkpoint files under the script folder by default.
+
+You will get the loss value as following:
+```
+# grep "loss is " out.train.log
+epoch: 1 step: 390, loss is 0.6003723
+epcoh: 2 step: 390, loss is 0.35312173
+...
+```
+
+### Evaluation
+
+```
+python eval.py --ckpt_path=./lstm-20-390.ckpt > out.eval.log 2>&1 & 
+```
+The above python command will run in the background, you can view the results through the file `out.eval.log`.
+
+You will get the accuracy as following:
+```
+# grep "acc" out.eval.log
+result: {'acc': 0.83}
+```
+
+## Usage:
+
+### Training
+```
+usage: train.py [--preprocess {true,false}] [--aclimdb_path ACLIMDB_PATH]
+                [--glove_path GLOVE_PATH] [--preprocess_path PREPROCESS_PATH]
+                [--ckpt_path CKPT_PATH] [--device_target {GPU,CPU}]
+
+parameters/options:
+  --preprocess          whether to preprocess data.
+  --aclimdb_path        path where the dataset is stored.
+  --glove_path          path where the GloVe is stored.
+  --preprocess_path     path where the pre-process data is stored.
+  --ckpt_path           the path to save the checkpoint file.
+  --device_target       the target device to run, support "GPU", "CPU".
+```
+
+### Evaluation
+
+```
+usage: eval.py [--preprocess {true,false}] [--aclimdb_path ACLIMDB_PATH]
+               [--glove_path GLOVE_PATH] [--preprocess_path PREPROCESS_PATH]
+               [--ckpt_path CKPT_PATH] [--device_target {GPU,CPU}]
+
+parameters/options:
+  --preprocess          whether to preprocess data.
+  --aclimdb_path        path where the dataset is stored.
+  --glove_path          path where the GloVe is stored.
+  --preprocess_path     path where the pre-process data is stored.
+  --ckpt_path           the checkpoint file path used to evaluate model.
+  --device_target       the target device to run, support "GPU", "CPU".
+```

example/lstm_aclImdb/config.py

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+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""
+network config setting
+"""
+from easydict import EasyDict as edict
+
+# LSTM CONFIG
+lstm_cfg = edict({
+    'num_classes': 2,
+    'learning_rate': 0.1,
+    'momentum': 0.9,
+    'num_epochs': 20,
+    'batch_size': 64,
+    'embed_size': 300,
+    'num_hiddens': 100,
+    'num_layers': 2,
+    'bidirectional': True,
+    'save_checkpoint_steps': 390,
+    'keep_checkpoint_max': 10
+})

example/lstm_aclImdb/dataset.py

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+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""
+Data operations, will be used in train.py and eval.py
+"""
+import os
+
+import numpy as np
+
+from imdb import ImdbParser
+import mindspore.dataset as ds
+from mindspore.mindrecord import FileWriter
+
+
+def create_dataset(data_home, batch_size, repeat_num=1, training=True):
+    """Data operations."""
+    ds.config.set_seed(1)
+    data_dir = os.path.join(data_home, "aclImdb_train.mindrecord0")
+    if not training:
+        data_dir = os.path.join(data_home, "aclImdb_test.mindrecord0")
+
+    data_set = ds.MindDataset(data_dir, columns_list=["feature", "label"], num_parallel_workers=4)
+
+    # apply map operations on images
+    data_set = data_set.shuffle(buffer_size=data_set.get_dataset_size())
+    data_set = data_set.batch(batch_size=batch_size, drop_remainder=True)
+    data_set = data_set.repeat(count=repeat_num)
+
+    return data_set
+
+
+def _convert_to_mindrecord(data_home, features, labels, weight_np=None, training=True):
+    """
+    convert imdb dataset to mindrecoed dataset
+    """
+    if weight_np is not None:
+        np.savetxt(os.path.join(data_home, 'weight.txt'), weight_np)
+
+    # write mindrecord
+    schema_json = {"id": {"type": "int32"},
+                   "label": {"type": "int32"},
+                   "feature": {"type": "int32", "shape": [-1]}}
+
+    data_dir = os.path.join(data_home, "aclImdb_train.mindrecord")
+    if not training:
+        data_dir = os.path.join(data_home, "aclImdb_test.mindrecord")
+
+    def get_imdb_data(features, labels):
+        data_list = []
+        for i, (label, feature) in enumerate(zip(labels, features)):
+            data_json = {"id": i,
+                         "label": int(label),
+                         "feature": feature.reshape(-1)}
+            data_list.append(data_json)
+        return data_list
+
+    writer = FileWriter(data_dir, shard_num=4)
+    data = get_imdb_data(features, labels)
+    writer.add_schema(schema_json, "nlp_schema")
+    writer.add_index(["id", "label"])
+    writer.write_raw_data(data)
+    writer.commit()
+
+
+def convert_to_mindrecord(embed_size, aclimdb_path, preprocess_path, glove_path):
+    """
+    convert imdb dataset to mindrecoed dataset
+    """
+    parser = ImdbParser(aclimdb_path, glove_path, embed_size)
+    parser.parse()
+
+    if not os.path.exists(preprocess_path):
+        print(f"preprocess path {preprocess_path} is not exist")
+        os.makedirs(preprocess_path)
+
+    train_features, train_labels, train_weight_np = parser.get_datas('train')
+    _convert_to_mindrecord(preprocess_path, train_features, train_labels, train_weight_np)
+
+    test_features, test_labels, _ = parser.get_datas('test')
+    _convert_to_mindrecord(preprocess_path, test_features, test_labels, training=False)

example/lstm_aclImdb/eval.py

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+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""
+#################train lstm example on aclImdb########################
+python eval.py --ckpt_path=./lstm-20-390.ckpt
+"""
+import argparse
+import os
+
+import numpy as np
+
+from config import lstm_cfg as cfg
+from dataset import create_dataset, convert_to_mindrecord
+from mindspore import Tensor, nn, Model, context
+from mindspore.model_zoo.lstm import SentimentNet
+from mindspore.nn import Accuracy
+from mindspore.train.callback import LossMonitor
+from mindspore.train.serialization import load_checkpoint, load_param_into_net
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='MindSpore LSTM Example')
+    parser.add_argument('--preprocess', type=str, default='false', choices=['true', 'false'],
+                        help='whether to preprocess data.')
+    parser.add_argument('--aclimdb_path', type=str, default="./aclImdb",
+                        help='path where the dataset is stored.')
+    parser.add_argument('--glove_path', type=str, default="./glove",
+                        help='path where the GloVe is stored.')
+    parser.add_argument('--preprocess_path', type=str, default="./preprocess",
+                        help='path where the pre-process data is stored.')
+    parser.add_argument('--ckpt_path', type=str, default=None,
+                        help='the checkpoint file path used to evaluate model.')
+    parser.add_argument('--device_target', type=str, default="GPU", choices=['GPU', 'CPU'],
+                        help='the target device to run, support "GPU", "CPU". Default: "GPU".')
+    args = parser.parse_args()
+
+    context.set_context(
+        mode=context.GRAPH_MODE,
+        save_graphs=False,
+        device_target=args.device_target)
+
+    if args.preprocess == "true":
+        print("============== Starting Data Pre-processing ==============")
+        convert_to_mindrecord(cfg.embed_size, args.aclimdb_path, args.preprocess_path, args.glove_path)
+
+    embedding_table = np.loadtxt(os.path.join(args.preprocess_path, "weight.txt")).astype(np.float32)
+    network = SentimentNet(vocab_size=embedding_table.shape[0],
+                           embed_size=cfg.embed_size,
+                           num_hiddens=cfg.num_hiddens,
+                           num_layers=cfg.num_layers,
+                           bidirectional=cfg.bidirectional,
+                           num_classes=cfg.num_classes,
+                           weight=Tensor(embedding_table),
+                           batch_size=cfg.batch_size)
+
+    loss = nn.SoftmaxCrossEntropyWithLogits(is_grad=False, sparse=True)
+    opt = nn.Momentum(network.trainable_params(), cfg.learning_rate, cfg.momentum)
+    loss_cb = LossMonitor()
+
+    model = Model(network, loss, opt, {'acc': Accuracy()})
+
+    print("============== Starting Testing ==============")
+    ds_eval = create_dataset(args.preprocess_path, cfg.batch_size, training=False)
+    param_dict = load_checkpoint(args.ckpt_path)
+    load_param_into_net(network, param_dict)
+    if args.device_target == "CPU":
+        acc = model.eval(ds_eval, dataset_sink_mode=False)
+    else:
+        acc = model.eval(ds_eval)
+    print("============== Accuracy:{} ==============".format(acc))

example/lstm_aclImdb/imdb.py

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+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""
+imdb dataset parser.
+"""
+import os
+from itertools import chain
+
+import gensim
+import numpy as np
+
+
+class ImdbParser():
+    """
+    parse aclImdb data to features and labels.
+    sentence->tokenized->encoded->padding->features
+    """
+
+    def __init__(self, imdb_path, glove_path, embed_size=300):
+        self.__segs = ['train', 'test']
+        self.__label_dic = {'pos': 1, 'neg': 0}
+        self.__imdb_path = imdb_path
+        self.__glove_dim = embed_size
+        self.__glove_file = os.path.join(glove_path, 'glove.6B.' + str(self.__glove_dim) + 'd.txt')
+
+        # properties
+        self.__imdb_datas = {}
+        self.__features = {}
+        self.__labels = {}
+        self.__vacab = {}
+        self.__word2idx = {}
+        self.__weight_np = {}
+        self.__wvmodel = None
+
+    def parse(self):
+        """
+        parse imdb data to memory
+        """
+        self.__wvmodel = gensim.models.KeyedVectors.load_word2vec_format(self.__glove_file)
+
+        for seg in self.__segs:
+            self.__parse_imdb_datas(seg)
+            self.__parse_features_and_labels(seg)
+            self.__gen_weight_np(seg)
+
+    def __parse_imdb_datas(self, seg):
+        """
+        load data from txt
+        """
+        data_lists = []
+        for label_name, label_id in self.__label_dic.items():
+            sentence_dir = os.path.join(self.__imdb_path, seg, label_name)
+            for file in os.listdir(sentence_dir):
+                with open(os.path.join(sentence_dir, file), mode='r', encoding='utf8') as f:
+                    sentence = f.read().replace('\n', '')
+                    data_lists.append([sentence, label_id])
+        self.__imdb_datas[seg] = data_lists
+
+    def __parse_features_and_labels(self, seg):
+        """
+        parse features and labels
+        """
+        features = []
+        labels = []
+        for sentence, label in self.__imdb_datas[seg]:
+            features.append(sentence)
+            labels.append(label)
+
+        self.__features[seg] = features
+        self.__labels[seg] = labels
+
+        # update feature to tokenized
+        self.__updata_features_to_tokenized(seg)
+        # parse vacab
+        self.__parse_vacab(seg)
+        # encode feature
+        self.__encode_features(seg)
+        # padding feature
+        self.__padding_features(seg)
+
+    def __updata_features_to_tokenized(self, seg):
+        tokenized_features = []
+        for sentence in self.__features[seg]:
+            tokenized_sentence = [word.lower() for word in sentence.split(" ")]
+            tokenized_features.append(tokenized_sentence)
+        self.__features[seg] = tokenized_features
+
+    def __parse_vacab(self, seg):
+        # vocab
+        tokenized_features = self.__features[seg]
+        vocab = set(chain(*tokenized_features))
+        self.__vacab[seg] = vocab
+
+        # word_to_idx: {'hello': 1, 'world':111, ... '<unk>': 0}
+        word_to_idx = {word: i + 1 for i, word in enumerate(vocab)}
+        word_to_idx['<unk>'] = 0
+        self.__word2idx[seg] = word_to_idx
+
+    def __encode_features(self, seg):
+        """ encode word to index """
+        word_to_idx = self.__word2idx['train']
+        encoded_features = []
+        for tokenized_sentence in self.__features[seg]:
+            encoded_sentence = []
+            for word in tokenized_sentence:
+                encoded_sentence.append(word_to_idx.get(word, 0))
+            encoded_features.append(encoded_sentence)
+        self.__features[seg] = encoded_features
+
+    def __padding_features(self, seg, maxlen=500, pad=0):
+        """ pad all features to the same length """
+        padded_features = []
+        for feature in self.__features[seg]:
+            if len(feature) >= maxlen:
+                padded_feature = feature[:maxlen]
+            else:
+                padded_feature = feature
+                while len(padded_feature) < maxlen:
+                    padded_feature.append(pad)
+            padded_features.append(padded_feature)
+        self.__features[seg] = padded_features
+
+    def __gen_weight_np(self, seg):
+        """
+        generate weight by gensim
+        """
+        weight_np = np.zeros((len(self.__word2idx[seg]), self.__glove_dim), dtype=np.float32)
+        for word, idx in self.__word2idx[seg].items():
+            if word not in self.__wvmodel:
+                continue
+            word_vector = self.__wvmodel.get_vector(word)
+            weight_np[idx, :] = word_vector
+
+        self.__weight_np[seg] = weight_np
+
+    def get_datas(self, seg):
+        """
+        return features, labels, and weight
+        """
+        features = np.array(self.__features[seg]).astype(np.int32)
+        labels = np.array(self.__labels[seg]).astype(np.int32)
+        weight = np.array(self.__weight_np[seg])
+        return features, labels, weight

example/lstm_aclImdb/train.py

@@ -0,0 +1,83 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""
+#################train lstm example on aclImdb########################
+python train.py --preprocess=true --aclimdb_path=your_imdb_path --glove_path=your_glove_path
+"""
+import argparse
+import os
+
+import numpy as np
+
+from config import lstm_cfg as cfg
+from dataset import convert_to_mindrecord
+from dataset import create_dataset
+from mindspore import Tensor, nn, Model, context
+from mindspore.model_zoo.lstm import SentimentNet
+from mindspore.nn import Accuracy
+from mindspore.train.callback import LossMonitor, CheckpointConfig, ModelCheckpoint, TimeMonitor
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='MindSpore LSTM Example')
+    parser.add_argument('--preprocess', type=str, default='false', choices=['true', 'false'],
+                        help='whether to preprocess data.')
+    parser.add_argument('--aclimdb_path', type=str, default="./aclImdb",
+                        help='path where the dataset is stored.')
+    parser.add_argument('--glove_path', type=str, default="./glove",
+                        help='path where the GloVe is stored.')
+    parser.add_argument('--preprocess_path', type=str, default="./preprocess",
+                        help='path where the pre-process data is stored.')
+    parser.add_argument('--ckpt_path', type=str, default="./",
+                        help='the path to save the checkpoint file.')
+    parser.add_argument('--device_target', type=str, default="GPU", choices=['GPU', 'CPU'],
+                        help='the target device to run, support "GPU", "CPU". Default: "GPU".')
+    args = parser.parse_args()
+
+    context.set_context(
+        mode=context.GRAPH_MODE,
+        save_graphs=False,
+        device_target=args.device_target)
+
+    if args.preprocess == "true":
+        print("============== Starting Data Pre-processing ==============")
+        convert_to_mindrecord(cfg.embed_size, args.aclimdb_path, args.preprocess_path, args.glove_path)
+
+    embedding_table = np.loadtxt(os.path.join(args.preprocess_path, "weight.txt")).astype(np.float32)
+    network = SentimentNet(vocab_size=embedding_table.shape[0],
+                           embed_size=cfg.embed_size,
+                           num_hiddens=cfg.num_hiddens,
+                           num_layers=cfg.num_layers,
+                           bidirectional=cfg.bidirectional,
+                           num_classes=cfg.num_classes,
+                           weight=Tensor(embedding_table),
+                           batch_size=cfg.batch_size)
+
+    loss = nn.SoftmaxCrossEntropyWithLogits(is_grad=False, sparse=True)
+    opt = nn.Momentum(network.trainable_params(), cfg.learning_rate, cfg.momentum)
+    loss_cb = LossMonitor()
+
+    model = Model(network, loss, opt, {'acc': Accuracy()})
+
+    print("============== Starting Training ==============")
+    ds_train = create_dataset(args.preprocess_path, cfg.batch_size, repeat_num=cfg.num_epochs)
+    config_ck = CheckpointConfig(save_checkpoint_steps=cfg.save_checkpoint_steps,
+                                 keep_checkpoint_max=cfg.keep_checkpoint_max)
+    ckpoint_cb = ModelCheckpoint(prefix="lstm", directory=args.ckpt_path, config=config_ck)
+    time_cb = TimeMonitor(data_size=ds_train.get_dataset_size())
+    if args.device_target == "CPU":
+        model.train(cfg.num_epochs, ds_train, callbacks=[time_cb, ckpoint_cb, loss_cb], dataset_sink_mode=False)
+    else:
+        model.train(cfg.num_epochs, ds_train, callbacks=[time_cb, ckpoint_cb, loss_cb])
+    print("============== Training Success ==============")

mindspore/model_zoo/lstm.py

@@ -0,0 +1,115 @@
+# Copyright 2020 Huawei Technologies Co., Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+"""LSTM."""
+import math
+
+import numpy as np
+
+from mindspore import Parameter, Tensor, nn
+from mindspore.common.initializer import initializer
+from mindspore.ops import operations as P
+
+
+def init_lstm_weight(
+        input_size,
+        hidden_size,
+        num_layers,
+        bidirectional,
+        has_bias=True):
+    """Initialize lstm weight."""
+    num_directions = 1
+    if bidirectional:
+        num_directions = 2
+
+    weight_size = 0
+    gate_size = 4 * hidden_size
+    for layer in range(num_layers):
+        for _ in range(num_directions):
+            input_layer_size = input_size if layer == 0 else hidden_size * num_directions
+            weight_size += gate_size * input_layer_size
+            weight_size += gate_size * hidden_size
+            if has_bias:
+                weight_size += 2 * gate_size
+
+    stdv = 1 / math.sqrt(hidden_size)
+    w_np = np.random.uniform(-stdv, stdv, (weight_size, 1, 1)).astype(np.float32)
+    w = Parameter(initializer(Tensor(w_np), [weight_size, 1, 1]), name='weight')
+
+    return w
+
+
+# Initialize short-term memory (h) and long-term memory (c) to 0
+def lstm_default_state(batch_size, hidden_size, num_layers, bidirectional):
+    """init default input."""
+    num_directions = 1
+    if bidirectional:
+        num_directions = 2
+
+    h = Tensor(
+        np.zeros((num_layers * num_directions, batch_size, hidden_size)).astype(np.float32))
+    c = Tensor(
+        np.zeros((num_layers * num_directions, batch_size, hidden_size)).astype(np.float32))
+    return h, c
+
+
+class SentimentNet(nn.Cell):
+    """Sentiment network structure."""
+
+    def __init__(self,
+                 vocab_size,
+                 embed_size,
+                 num_hiddens,
+                 num_layers,
+                 bidirectional,
+                 num_classes,
+                 weight,
+                 batch_size):
+        super(SentimentNet, self).__init__()
+        # Mapp words to vectors
+        self.embedding = nn.Embedding(vocab_size,
+                                      embed_size,
+                                      embedding_table=weight)
+        self.embedding.embedding_table.requires_grad = False
+        self.trans = P.Transpose()
+        self.perm = (1, 0, 2)
+        self.encoder = nn.LSTM(input_size=embed_size,
+                               hidden_size=num_hiddens,
+                               num_layers=num_layers,
+                               has_bias=True,
+                               bidirectional=bidirectional,
+                               dropout=0.0)
+        w_init = init_lstm_weight(
+            embed_size,
+            num_hiddens,
+            num_layers,
+            bidirectional)
+        self.encoder.weight = w_init
+        self.h, self.c = lstm_default_state(batch_size, num_hiddens, num_layers, bidirectional)
+
+        self.concat = P.Concat(1)
+        if bidirectional:
+            self.decoder = nn.Dense(num_hiddens * 4, num_classes)
+        else:
+            self.decoder = nn.Dense(num_hiddens * 2, num_classes)
+
+    def construct(self, inputs):
+        # input：(64,500,300)
+        embeddings = self.embedding(inputs)
+        embeddings = self.trans(embeddings, self.perm)
+        output, _ = self.encoder(embeddings, (self.h, self.c))
+        # states[i] size(64,200)  -> encoding.size(64,400)
+        encoding = self.concat((output[0], output[1]))
+        outputs = self.decoder(encoding)
+        return outputs