Test Model is showing Error

 I have  applied model.fit function with validation data and no of epoch = 5. 

I got nearly 97% accuracy.

When I tried evaluate model on test data, it shows error - ''>' not supported between instances of 'NoneType' and 'int''. 

Can anyone suggest solution of it ?

NUM_EPOCHS = 5

model.fit(train_data,epochs = NUM_EPOCHS,validation_data=(validation_inputs,validation_targets),
         verbose=2);

test_loss,test_accuracy = model.evaluate(test_data)