code: def defaults(self_):
          
          self = self_.self
          d = {}
          for param_name,param in self.param.objects('existing').items():
              if param.constant:
                  pass
              elif param.instantiate:
                  self.param._instantiate_param(param,dict_=d,key=param_name)
              else:
                  d[param_name]=param.default
          return d
docs: Return {parameter_name:parameter.default} for all non-constant
          Parameters.
  
          Note that a Parameter for which instantiate==True has its default
          instantiated.