def METHOD_NAME(self, var_list):
    super().METHOD_NAME(var_list)
    if hasattr(self, "_built") and self._built:
        return
    self._built = True
    self._accumulated_grads = []
    self._accumulated_delta_vars = []
    for var in var_list:
        self._accumulated_grads.append(
            self.add_variable_from_reference(var, "accumulated_grad")
        )
        self._accumulated_delta_vars.append(
            self.add_variable_from_reference(var, "accumulated_delta_var")
        )