defineCallbacks

save_model_callback = ModelCheckpoint(DIRECTORY_TRAINED_MODEL,
                                      verbose=1,
                                      save_best_only=True,
                                      save_weights_only=False,
                                      mode='auto',
                                      period=1,
                                      monitor='val_acc')

early_stopping = EarlyStopping(verbose=1,monitor='val_acc', min_delta=0, patience=3, mode='auto')