code: def _run_on_loss(self, net, param_init_net, param, grad=None):
      return None
  
imports: from caffe2.python import core, utils
  import numpy
label_desc: Use image node_id 3 for calling the Regularizer obj's underlying member method code with example usage: obj._run_on_loss(net, param_init_net, param, grad) and returns: None