title: “IndexError: too many indices for array” in array expanding
body: <pre><code> ima = np.array(image)
   ima2 = ima[:,:,0]
   ima = np.insert(ima, 3, values=ima2, axis=2)
  </code></pre>
  
  <p>I'm encountering this error when I try to expand an <code>(224,224,3)</code> array into <code>(224,224,4)</code> in a vgg training code. But interestingly there is no error if only it is executed.</p>
  
  <p>I don't understand what's wrong. Any help would be appreciated.</p>