title: How to clear out/delete tensors in tensorflow?
body: <p>As I understand, <code>tf.reset_default_graph()</code> only creates a new graph and sets it equal to the default graph. So, the previously created tensors would just be lying around occupying the memory. I have also read the unreferenced tensors are not garbage collected (like normal variables in Python are). </p>
  
  <p>If I am running a cross-validation to search for a set of hyperparameters and thus creating the same graph, again and again, how do I get rid of the previously created tensors?</p>