code: def _degree_signal(in_degrees, out_degrees, bias_val, decay):
      """Signal on the degrees."""
      avg_degree = (in_degrees.mean() + out_degrees.mean()) / 2.0
      return np.exp(-decay * abs(avg_degree - bias_val))
  
file_path: dragonfly/dragonfly/nn/syn_nn_functions.py
imports: import numpy
label_desc: Use image node_id 3 for calling a global function with example usage: _degree_signal(in_degrees, out_degrees, bias_val, decay) and returns: np