add condition if act None (#17)

utils.py

@@ -42,7 +42,10 @@ def normalize(inp, activation, reuse, scope):
     elif FLAGS.norm == 'layer_norm':
         return tf_layers.layer_norm(inp, activation_fn=activation, reuse=reuse, scope=scope)
     elif FLAGS.norm == 'None':
-        return activation(inp)
+        if activation is not None:
+            return activation(inp)
+        else:
+            return inp
 
 ## Loss functions
 def mse(pred, label):
@@ -53,5 +56,3 @@ def mse(pred, label):
 def xent(pred, label):
     # Note - with tf version <=0.12, this loss has incorrect 2nd derivatives
     return tf.nn.softmax_cross_entropy_with_logits(logits=pred, labels=label) / FLAGS.update_batch_size
-
-