title: How do I know which version of the Keras API is implemented in tf.keras?
body: <p>In the standard implementation of Keras, one can get the API version using <a href="https://stackoverflow.com/q/46086030/1735003"><code>keras.__version__</code></a>.</p>
  
  <p>However, there is no <code>tf.keras.__version__</code>.</p>
  
  <p>So how do I check the version of the Keras API implemented in <code>tf.keras</code>?</p>