title: Is it necessary to close session after tensorflow InteractiveSession()
body: <p>I have a question about <code>InteractiveSession</code> in Tensorflow</p>
  
  <p>I know <code>tf.InteractiveSession()</code> is just convenient syntactic
  sugar for keeping a default session open and basically work the same like below:</p>
  
  <pre><code>with tf.Session() as sess:
      # Do something
  </code></pre>
  
  <p>However, I have seen some examples online, they did't call <code>close()</code> at the end of the code after using <code>InteractiveSession</code>.</p>
  
  <p><strong>Question</strong>:<br>
  1. Would it caused any problem without closing the session like session leak? <br>
  2. How the GC work for the InteractiveSession if we don't close it?</p>