title: AttributeError: module 'tensorflow.python.layers.layers' has no attribute 'Layer'
body: <p>I'm learning an article called "Attention is all you need", and I'm Trying to learn the code (of the official article from github), and I'm getting weird error, the error is: 
  "AttributeError: module 'tensorflow.python.layers.layers' has no attribute 'Layer'"</p>
  
  <p>The code generating the error:</p>
  
  <pre><code>from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  
  import tensorflow as tf
  class Attention(tf.layers.Layer)://this is the line the generating the error
  </code></pre>
  
  <p>Now this is weird because when checking online, all the solutions were version problem of tensorflow, and I have a sufficient version (by the answers online) 1.7.0, Also my python version is 3.6.4.</p>
  
  <p>One more thing is it normal that in the error description it's written:"tensorflow.python.layers.layers" and not just "tensorflow.layers"?</p>
  
  <p>Thanks a lot for your help.</p>