code: def softplus_activation_function(x):
      r"""
      Applies the softplus function:
  
      .. math::
  
          \begin{align*}
              y=\log(\exp(x)+1)
          \end{align*}
  
      """
      return log(exp(x) + 1)
  
imports: from pyomo.environ import exp, log, tanh
label_desc: Use image node_id 1 for calling a global function with example usage: softplus_activation_function(x) and returns: log