adding lstm option for RNN

toolkit.py

@@ -34,7 +34,7 @@ from sklearn.externals import joblib
 from sklearn.metrics import roc_curve, auc
 from sklearn.utils.extmath import stable_cumsum
 from keras.models import Sequential, Model, model_from_json
-from keras.layers import Dense, Dropout, Input, Masking, GRU, concatenate, SimpleRNN
+from keras.layers import Dense, Dropout, Input, Masking, GRU, LSTM, concatenate, SimpleRNN
 from keras.callbacks import History, EarlyStopping, CSVLogger, ModelCheckpoint, TensorBoard
 from keras.optimizers import SGD
 import keras.optimizers
@@ -1736,6 +1736,8 @@ class ClassificationProjectRNN(ClassificationProject):
                     channel = GRU(self.rnn_layer_nodes)(channel)
                 elif self.recurrent_unit_type == "SimpleRNN":
                     channel = SimpleRNN(self.rnn_layer_nodes)(channel)
+                elif self.recurrent_unit_type == "LSTM":
+                    channel = LSTM(self.rnn_layer_nodes)(channel)
                 else:
                     raise NotImplementedError("{} not implemented".format(self.recurrent_unit_type))
                 logger.info("Added {} unit".format(self.recurrent_unit_type))