Merge pull request #51 from AmeerHajAli/patch-1

tensorflow 2.0 not having attribute python

Author: urialon

keras_attention_layer.py

@@ -1,7 +1,7 @@
 import tensorflow as tf
 from tensorflow.python import keras
 from tensorflow.python.keras.layers import Layer
-import tensorflow.python.keras.backend as K
+from tensorflow.python.keras import backend as K
 from typing import Optional