title: definition of caffe.Layer class
body: <p>When defining a python layer in Caffe like <a href="https://github.com/snapfinger/fcn.berkeleyvision.org/blob/master/voc_layers.py" rel="nofollow noreferrer">this</a>, there are fields like <code>voc_dir</code>, <code>split</code>,<code>random</code>, etc, some of them are said to inherit from <code>caffe.Layer</code> class. </p>
  
  <p>However where can I find the definition of <code>caffe.Layer</code> class? Searched through Caffe's documentation but they provide very little explanation, and didn't find it after looking in several directories in their code base.</p>