code: def softmax(values):
      
      e_values = list(map(exp, values))
      s = sum(e_values)
      inv_s = 1.0 / s
      return [ev * inv_s for ev in e_values]
docs: Compute the softmax of the given value set, v_i = exp(v_i) / s,
      where s = sum(exp(v_0), exp(v_1), ..).