code: def _ref_log_softmax(values):
      max_val = np.max(values)  # for numerical stability
      stabilized_values = values - max_val
      log_sum_exp = np.log(np.sum(np.exp(stabilized_values)))
      return stabilized_values - log_sum_exp
  
imports: import numpy
  from keras import activations
  from keras import backend
  from keras import testing
label_desc: Use image node_id 3 for calling a global function with example usage: _ref_log_softmax(values) and returns: unknown