title: Save Keras model at specific epochs
body: <p>I am using Keras to do some training on my dataset and it is time consuming to keep running every time to locate the number of epochs needed to get the best results. I tried using callbacks to get the best model, but it just does not work and usually stops too early. Also, saving every N epochs is not an option for me.</p>
  
  <p>What I am trying to do is save the model after some specific epochs are done. Let's say for example, after <code>epoch = 150</code> is over, it will be saved as <code>model.save(model_1.h5)</code> and after <code>epoch = 152</code>, it will be saved as <code>model.save(model_2.h5)</code> etc... for few specific epochs.</p>
  
  <p>Is there a way to implement this in Keras ? I already searched for a method but no luck so far. </p>
  
  <p>Thank you for any help/suggestion.</p>